DRM stations
Teddy Bear
shortwave station? I mean listening to stations located thousands of miles.
I've been reading that there will be many new radio receivers next year DRM
capable.
Is there an online list of DRM stations all over the world?
Cheers.
RHF
.
.
. .
sdan...@nyc.rr.com
Yes, there are some DRM broadcasts to listen to. I suggest you act
fast, though, and if you buy a receiver get one that performs well with
ordinary shortwave broadcasts, since that's what you'll be listening to
after DRM disappears.
Steve
Harveya...@aol.com
>Yes, there are some DRM broadcasts to listen to. I suggest you
Lact fast, though, and if you buy a receiver get one that performs
>well with ordinary shortwave broadcasts, since that's what you'll >be listening to after DRM disappears.
Yes, this may be true . . Fuel costs are making basic Shortwave
broadcasting expensive;
adding fancy new transmitters to the Budget probably isn't in the
caards for many..
UNLESS.. people adopt the WBCQ Model of Wind generated
electricity for Transmitters . . ..
dxAce
Dennis
TLoewenberg
Where's Mihigan?
>
> dxAce
> Mihigan
> USA
>
>
cuh...@webtv.net
cuhulin
dxAce
cuh...@webtv.net wrote:
> Mihigan is across Lake Mihigan from Illinoys.
That's correct, I'm very near Lake Mihigan, and just a couple of blocks from
Lake Maatawa.
dxAce
Mihigan
USA
Michael A. Terrell
2.23 miles NNW of 'tardville, of course.
--
?
Michael A. Terrell
Central Florida
cuh...@webtv.net
Towering Investor.If New Orleans is going to be rebuilt like that,I
don't like it at all.One Las Vegas (I don't have anything again't Las
Vegas,Nevada,I haven't ever even been there before) in America is more
than enough and I don't want a "Las Vegas" 180 miles South of me.I want
New Orleans put back the way it was before Katrina.
cuhulin
RHF
.
ABOUT - Digital Radio Mondiale (DRM)
DRM => http://www.drm.org/.
.
Live Digital Radio Mondiale (DRM) Broadcast Schedule
DRM => http://www.drm.org/livebroadcast/livebroadcast.php
For International, National and Local DRM Broadcasts
Underway in Markets Worldwide
.
Digital Radio Mondiale (DRM) Broadcast Schedule {Links}
WWDXC => http://www.wwdxc.de/drm.htm
DRM => http://baseportal.com/baseportal/drmdx/main
.
Radio Netherlands List of Digital Radio Mondiale
(DRM) Broadcasts Scheduled
http://www2.rnw.nl/rnw/en/features/media/dossiers/drm_schedule.html
.
Radio Canada International (RCI) Transmitters
Digital Radio Mondiale (DRM) Broadcast Schedule
RCI - DRM => http://www.rcinet.ca/rci/PDF/drm.pdf
.
Deutsche Welle (DW) Germany
Digital Radio Mondiale (DRM) Broadcast Schedule
http://www.dw-world.de/dw/article/0,1564,1313929,00.html
.
Digital Radio Mondiale (DRM) - from Wikipedia
http://en.wikipedia.org/wiki/Digital_Radio_Mondiale
.
Digital Radio Mondiale (DRM) Discussion Group on YAHOO !
http://groups.yahoo.com/group/DRM-L/
.
.
yes - more than your wanted to know about : drm ~ RHF
.
.
. .
Telamon
"RHF" <rhf-new...@pacbell.net> wrote:
> For One and All,
> .
> ABOUT - Digital Radio Mondiale (DRM)
> DRM => http://www.drm.org/.
ALL you need to know is that the implementation was screwed up and over
hyped.
OH YEAH and it was lied about a lot buy the DRM organization.
AND it takes up more bandwidth than it was supposed too.
BUT it is just another system than the current analog with its mixed bag
of pluses and minuses, which make it no better than the current analog
system so why change to it?
--
Telamon
Ventura, California
Frank Dresser
[snip]
>
> BUT it is just another system than the current analog with its mixed bag
> of pluses and minuses, which make it no better than the current analog
> system so why change to it?
>
> --
> Telamon
> Ventura, California
Why change? Because:
"DRM can be used for a range of audio content, including multi-lingual
speech and music."
http://drm.org/system/technicalaspect.php
Just try that with some old-fashioned analog system.
"There is a global trend towards the adoption of digital technology in radio
and communications, especially for distribution and transmission. "
And:
"However, the limited fidelity of existing AM services is causinglisteners
to search for other alternatives."
http://drm.org/system/whydigital.php
Well, I'm confused on this point. Didn't AM became obselete in the forties
with the introduction of FM? If I remember my history correctly, didn't all
the limited fidelity AM stations go bankrupt as all their listeners were
drawn to high fidelity FM?
It seems limited fidelity AM is in for it again:
"DRM is the only universal, non-proprietary digital AM radio system with
near-FM quality sound available to markets worldwide."
There ya have it. DRM has both "near-FM quality sound" and digital
trendiness.
I can't think of any better reasons for the listener to care.
Frank Dresser
Kristoff Bonne
Telamon schreef:
>>For One and All,
>>ABOUT - Digital Radio Mondiale (DRM)
>>DRM => http://www.drm.org/.
> ALL you need to know is that the implementation was screwed up and over
> hyped.
> OH YEAH and it was lied about a lot buy the DRM organization.
> AND it takes up more bandwidth than it was supposed too.
> BUT it is just another system than the current analog with its mixed bag
> of pluses and minuses, which make it no better than the current analog
> system so why change to it?
Aren't you mixing up DRM with IBOC-AM?
DRM might bring people back to LW/MW/SW and they might not even know it.
One of the things with DRM (and especially with the DAB/DRM chipset now
available) is that the user will just be presented with a list of
stations and he will just have to pick the one from the list. She will
not know if she is listening to a DAB broadcast at 1.4 Ghz or long-wave
at below 200 Khz.
DRM has two major advantages:
- it does away with fading, which is one of the things people find most
annoying about LW/MW/SW.
The "audio-quality" aspect is a bit mood as it all depends on what mode
you are using and I think for most people is not the most important
element. But if you produce a stable signal without fading, this would
make LW/MW/SW broadcasts quite acceptable by most people.
(The term "near-FM" is marketing talk, just ignore it).
- It allows broadcasters to break into certain markets by broadcasting
from abroad. BCE (RTL's broadcasting arm) plan to use it to broadcast
using DRM on LW, MW and SW towards different countries.
The new frequencies on LW and MW they have requested at the ITU are 279
Khz (Junglinster towards Germany), 567 Khz (Clervoux towards the
Netherlands), 783 Khz (Beidweiler towards France) and 1098 Khz (Clervoux
towards Belgium).
For SW, they have asked the HFCC for coordination for two frequencies:
5990 and 6095 Khz.
Cheerio! Kr. Bonne.
dxAce
Kristoff Bonne wrote:
Cheerio my ass. DRM = QRM any which way you slice it or dice it.
dxAce
Michigan
USA
Frank Dresser
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
news:432ea550$0$29276$ba62...@news.skynet.be...
>
>
> DRM has two major advantages:
> - it does away with fading, which is one of the things people find most
> annoying about LW/MW/SW.
DRM cannot do away with fading. I have no doubt that a DRM listener won't
notice minor fading, but major fading will cause drop-outs, rather than fade
outs. I think most listeners would find drop-outs more jarring than fade
outs. Either way, it will still be an annoyance.
Every once in a while, there just is no SW signal progagation at all. DRM
signals won't get through any better on those no signal times than analog
signals do.
> The "audio-quality" aspect is a bit mood as it all depends on what mode
> you are using and I think for most people is not the most important
> element. But if you produce a stable signal without fading, this would
> make LW/MW/SW broadcasts quite acceptable by most people.
LW and MW analog broadcasts are usually quite acceptable within their ground
wave coverage area. Skywave progagation is sometimes a problem. DRM may,
or may not, reduce those problems.
People will know a particular radio station is on SW whenever it drops out
or just never shows up. Or they will blame the radio station. Or their DRM
radio.
I really don't think SW radio will ever achieve mainstream popularity,
whatever modulation scheme is used.
>
> (The term "near-FM" is marketing talk, just ignore it).
Why do the DRM proponents make such a big issue of "near-FM" audio? Is that
really one of thier best arguements for DRM?
>
>
> - It allows broadcasters to break into certain markets by broadcasting
> from abroad. BCE (RTL's broadcasting arm) plan to use it to broadcast
> using DRM on LW, MW and SW towards different countries.
I suppose there might be signal to noise advantages in fringe ground wave
areas on LW and MW. There would be economic advantages if they can get the
same signal to noise ratio at reduced power. Reducing power on LW and MW
should reduce interference areas where the radio landscape is crowded. So,
DRM might have some advantages on LW and MW in such places as Europe.
I still don't see any strong advantages on SW, which will always have uneven
propagation.
>
> The new frequencies on LW and MW they have requested at the ITU are 279
> Khz (Junglinster towards Germany), 567 Khz (Clervoux towards the
> Netherlands), 783 Khz (Beidweiler towards France) and 1098 Khz (Clervoux
> towards Belgium).
>
> For SW, they have asked the HFCC for coordination for two frequencies:
> 5990 and 6095 Khz.
>
>
>
> Cheerio! Kr. Bonne.
Frank Dresser
Greg
> From: dxAce <dx...@milestones.com>
> Organization: Wassamatta U.
> Newsgroups: rec.radio.shortwave
> Date: Mon, 19 Sep 2005 07:54:02 -0400
> Subject: Re: ABOUT - Digital Radio Mondiale (DRM) => http://www.drm.org/
>
>
> Cheerio my ass.
>
Priceless!
Greg
cuh...@webtv.net
born on November 5,1941 and I have been listening to AM Radio since
November 5,1941 and AM Radio has always been there.I don't believe AM
Radio and FM Radio and Shortwave Radio and Ham Radio will ever be
obsolete.
cuhulin
cuh...@webtv.net
cuhulin
Kristoff Bonne
>>DRM has two major advantages:
>>- it does away with fading, which is one of the things people find most
>>annoying about LW/MW/SW.
> DRM cannot do away with fading. I have no doubt that a DRM listener won't
> notice minor fading, but major fading will cause drop-outs, rather than fade
> outs. I think most listeners would find drop-outs more jarring than fade
> outs. Either way, it will still be an annoyance.
True, but -as you indicate- as long as the C/N ratio is good enough and
the FEC knows how to handle the error, the listener will not notice
anything.
In that way, it is like FM that is has a much more steep threshold where
the signal remains constant for the listener.
> Every once in a while, there just is no SW signal progagation at all. DRM
> signals won't get through any better on those no signal times than analog
> signals do.
In the future, digital techniques will deal with this.
Look at how the US satellite radio-systems deal with this. There is no
indication that you only need to have a single source.
Quite a lot of shortwave station broadcast at more then one frequency at
a time so it possible to have a radio tuned to two frequencies at the
same time and let the radio "interleave" the signals from two sources
when one of the has a drop-out.
(DRM includes "alternative frequency" information, so the receiver is
able to find out these additional signals by itself).
The choice is upto the broadcaster if he wants to pay for the additional
cost of this. (It will probably be that this is only needed during
certain times of the day).
>>The "audio-quality" aspect is a bit mood as it all depends on what mode
>>you are using and I think for most people is not the most important
>>element. But if you produce a stable signal without fading, this would
>>make LW/MW/SW broadcasts quite acceptable by most people.
> LW and MW analog broadcasts are usually quite acceptable within their ground
> wave coverage area. Skywave progagation is sometimes a problem. DRM may,
> or may not, reduce those problems.
There was an additonal mode added to DRM designed to handle the
propagation of NVIS; which are worse than the "normal" propagation-problems.
> People will know a particular radio station is on SW whenever it drops out
> or just never shows up. Or they will blame the radio station. Or their DRM
> radio.
> I really don't think SW radio will ever achieve mainstream popularity,
> whatever modulation scheme is used.
We will see. If DRM works well for most of the time and additional
stations have interesting content, people will get one of these
"RTL-radios" (which will happen to be a DRM-radio and which happens to
work on shortwave-frequencies).
>>(The term "near-FM" is marketing talk, just ignore it).
> Why do the DRM proponents make such a big issue of "near-FM" audio? Is that
> really one of thier best arguements for DRM?
Beats me. Because it is the argument what most "normal" people
understand best. "It does away with fading" is something most people do
not understand as most of them do not listen to SW anymore anyway.
>>- It allows broadcasters to break into certain markets by broadcasting
>>from abroad. BCE (RTL's broadcasting arm) plan to use it to broadcast
>>using DRM on LW, MW and SW towards different countries.
> I suppose there might be signal to noise advantages in fringe ground wave
> areas on LW and MW. There would be economic advantages if they can get the
> same signal to noise ratio at reduced power. Reducing power on LW and MW
> should reduce interference areas where the radio landscape is crowded. So,
> DRM might have some advantages on LW and MW in such places as Europe.
For RTL, the reason is pretty simple. They see that people are moving
away from MW and LW to FM just because FM sounds that much better.
But getting a FM-licence for just a new radio-station is not that
simple. (you are dependent of the policy of every country involved).
In additonal, in some regions (like for their German market) it allows
them to cover a large part of the country with one single radio-station
from abroad which is impossible as the media is organised on the level
of the "Lander" and not on federal level in Germany.
DRM allows them to start up new stations without them being subject to
the legislation of all these individual countries and if DRM provides
them with "FM-like" quality (whatever that might be), that will probably
be good enough to keep people tuned to *their* stations and not move to
FM-stations.
> I still don't see any strong advantages on SW, which will always have uneven
> propagation.
We will see, but as DMR is a digital broadcasting-system, you can expect
additional improvements in the receivers too.
> Frank Dresser
Cheerio! Kr. Bonne.
Kristoff Bonne
Kristoff Bonne schreef:
>> Every once in a while, there just is no SW signal progagation at all.
>> DRM
>> signals won't get through any better on those no signal times than analog
>> signals do.
> In the future, digital techniques will deal with this.
> Look at how the US satellite radio-systems deal with this. There is no
> indication that you only need to have a single source.
> Quite a lot of shortwave station broadcast at more then one frequency at
> a time so it possible to have a radio tuned to two frequencies at the
> same time and let the radio "interleave" the signals from two sources
> when one of the has a drop-out.
Come to think of it. Why use different frequencies? DRM is able to
handle SFNs (single frequency networks)!
If you would broadcast your signal from (say) two or three different
transmittor-sites, if fading causes one of the signals to drop away, the
signal from the other site(s) will continue to be received.
It would be interesting to see how much power you would need from these
three transmittors together compaired to how much is needed if you only
use a single transmittor.
In the VHF-range, single-frequency networks allow for lower
transmission-power.
(due to the fact that the radio-signal is broadcast from multiple
points, a receiver will receive radio-signals from different directions
so there is more change of a signal coming in with a good quality).
It would be interesting to know if the same thing applies for HF!
Cheerio! Kr. BBonne.
Andrew Oakley
<analo...@worldnet.att.net> wrote:
>DRM cannot do away with fading. I have no doubt that a DRM listener won't
>notice minor fading, but major fading will cause drop-outs, rather than fade
>outs. I think most listeners would find drop-outs more jarring than fade
>outs. Either way, it will still be an annoyance.
Yes, yes yes. From my experience of analogue to digital terrestrial
television (DTT) here in the UK:
* What the marketting bods in major cities think is "acceptable"
and
* What country folk like myself are prepared to watch/listen to, in
order to get more choice
...are two very different things.
I'd quite happily listen to fading AM-SW and drop-out DTT if that
means I get more choice of the stuff I want (in my case, international
news).
But I'd be a lot happier if the marketting people sold this on choice
and ease-of-use rather than perfection of audio quality.
If I want to listen to music, I'll put on my MP3 player. I don't want
music on the radio, and even if I did, I sincerely doubt I'd find a
station playing exactly what I like (which is German techno, of which
I have plenty on my MP3 player). With the prevalence of MP3 players
these days, I really cannot imagine why anyone would want to listen to
the radio for music.
So the radio just has to be good enough quality to hear *speech*.
I even download comedy/drama to my MP3 player. My radio really is just
for *news*. And it so happens that I can get lots of news from lots of
international viewpoints using shortwave, all in acceptable *enough*
quality to hear what they're saying.
Of course with broadband everywhere in the UK, even in rural areas,
the whole city/country divide has almost gone. If I'm in my house or
my shed, I can listen to anything I like as streamed audio over the
Internet. But the reason I like radio is because it follows me
everywhere; and I can't (affordably, yet) stream network audio from my
car or whilst going for a country walk or whichever cheap & cheerful
hotel/cottage I'm having a business/vacation trip to.
Now if I could listen to international news from lots of different
viewpoints without having to hook up a ten-metre random wire antenna,
THEN I'd be interested. Does DRM do that?
--
Andrew Oakley andrew/atsymbol/aoakley/stop/com
Gloucestershire, UK
cuh...@webtv.net
Los Angeles or San Francisco or Sacremento,many other radio stations
come in better,Memphis,Nashville,Dallas,Fort
Worth,St.Louis,Denver,Detroit,Chicago,Pittsburgh,Des
Moines,Minneapolis,Atlanta,Cincinatti,Louisville,New
Orleans,Shreveport,Oklahoma City,many other long distance radio
stations,Sure,they fade in and out sometimes,but I often pick them
up.Show me a radio (with it's own built in antenna) that will pick up
that radio station in Monticello,Mississippi from my home here in the
West side of Jackson,Mississippi and I will buy it.
cuhulin
cuh...@webtv.net
A..holes force us to have to get on HDTV.Who wants to look at those ugly
blemishes and crappy looking hollyweird movie stars in such detail
anyway? I Don't! I Love Analog.
cuhulin
cuh...@webtv.net
cuhulin
cuh...@webtv.net
cuhulin
cuh...@webtv.net
cuhulin
cuh...@webtv.net
cuhulin
Frank Dresser
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
> Gegroet,
>
>
>
[snip]
>
> Quite a lot of shortwave station broadcast at more then one frequency at
> a time so it possible to have a radio tuned to two frequencies at the
> same time and let the radio "interleave" the signals from two sources
> when one of the has a drop-out.
>
> (DRM includes "alternative frequency" information, so the receiver is
> able to find out these additional signals by itself).
That's diversity reception. Diversity reception is almost as old as SW
radio, but it never has been popular with the public. I can imagine
diversity reception would be easier to do digitially, but diversity
reception doesn't always help. There will be moments in which propagation
will be bad on all frequencies, and longer times, such as during solar flare
events, in which SW will be useless.
>
>
>
> The choice is upto the broadcaster if he wants to pay for the additional
> cost of this. (It will probably be that this is only needed during
> certain times of the day).
>
>
>
[snip]
>
> We will see. If DRM works well for most of the time and additional
> stations have interesting content, people will get one of these
> "RTL-radios" (which will happen to be a DRM-radio and which happens to
> work on shortwave-frequencies).
SW radio works well most of the time, at least in the target areas. Let's
say a target area gets good reception 95% of the time. How much more
reliable might the reception be with DRM? 98%? 99%? Will 99% reliable
reception be good enough for non-hobbyists? I really don't think so.
>
> > Why do the DRM proponents make such a big issue of "near-FM" audio? Is
that
> > really one of thier best arguements for DRM?
>
> Beats me. Because it is the argument what most "normal" people
> understand best. "It does away with fading" is something most people do
> not understand as most of them do not listen to SW anymore anyway.
True. Normal people don't have a strong interest in high fidelity radio.
They consider thier radios to be appliances. And they want their radios to
work as easily and reliably as their refrigerators and stoves. They don't
want to hear anything about the ionosphere, interference from halfway around
the world, weird propagation and solar flares.
[snip]
>
> For RTL, the reason is pretty simple. They see that people are moving
> away from MW and LW to FM just because FM sounds that much better.
> But getting a FM-licence for just a new radio-station is not that
> simple. (you are dependent of the policy of every country involved).
>
> In additonal, in some regions (like for their German market) it allows
> them to cover a large part of the country with one single radio-station
> from abroad which is impossible as the media is organised on the level
> of the "Lander" and not on federal level in Germany.
>
> DRM allows them to start up new stations without them being subject to
> the legislation of all these individual countries and if DRM provides
> them with "FM-like" quality (whatever that might be), that will probably
> be good enough to keep people tuned to *their* stations and not move to
> FM-stations.
Won't the European Union standardize some of these bureaucratic problems?
Is there really much advantage to having one transmitter covering a huge
area? In the US, stations are individualized to the extent that they
usually carry the news, traffic and weather for their local market.
> We will see, but as DMR is a digital broadcasting-system, you can expect
> additional improvements in the receivers too.
The performance of analog radios could have been improved, if people wanted
to pay for the improvements. The real improvements in analog radios over
the last few years has been in price.
Frank Dresser
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
>
>
> Come to think of it. Why use different frequencies? DRM is able to
> handle SFNs (single frequency networks)!
>
> If you would broadcast your signal from (say) two or three different
> transmittor-sites, if fading causes one of the signals to drop away, the
> signal from the other site(s) will continue to be received.
>
> It would be interesting to see how much power you would need from these
> three transmittors together compaired to how much is needed if you only
> use a single transmittor.
>
>
> In the VHF-range, single-frequency networks allow for lower
> transmission-power.
> (due to the fact that the radio-signal is broadcast from multiple
> points, a receiver will receive radio-signals from different directions
> so there is more change of a signal coming in with a good quality).
>
> It would be interesting to know if the same thing applies for HF!
>
>
>
> Cheerio! Kr. BBonne.
It's worth remembering all the commercial SW data and phone links which were
in use before the satellite era. They had diversity reception,
sophisticated (for the time) digital modes, high power transmitters, high
gain antennas, etc. Yet they abandoned their large investment in SW as
satellites became available. Even with all their technology, SW still
wasn't reliable enough.
I think the average person expects at least the same order of reliablity
from their radios.
Frank Dresser
dxAce
Frank Dresser wrote:
> "Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
> news:432ebd07$0$345$ba62...@news.skynet.be...
> > Gegroet,
> >
> >
> >
> [snip]
>
> >
> > Quite a lot of shortwave station broadcast at more then one frequency at
> > a time so it possible to have a radio tuned to two frequencies at the
> > same time and let the radio "interleave" the signals from two sources
> > when one of the has a drop-out.
> >
> > (DRM includes "alternative frequency" information, so the receiver is
> > able to find out these additional signals by itself).
>
> That's diversity reception.
Do a Google on diversity reception.
dxAce
Michigan
USA
dxAce
Frank Dresser wrote:
One thing is certain, and that is if one is a radio hobbyist DRM is not your
friend. DRM = QRM.
Bearing that in mind, anyone who touts DRM is not your friend. They are your
enemy.
Die DRM, die.
dxAce
Michigan
USA
cuh...@webtv.net
of Daytona Beach made him take it down.About a week ago when I went to
the Celticfest Mississippi thingy at the Agricultural and Farm museum
thingy,I saw a wind generator on a tall steel tower,I took a picture of
it too.Yeah,you put up a wind generator on your property and watch your
neighbors start raseing h..l and the stinking city make you take it
down.
cuhulin
sdan...@nyc.rr.com
Frank Dresser wrote:
> Why change? Because:
>
> "DRM can be used for a range of audio content, including multi-lingual
> speech and music."
>
> http://drm.org/system/technicalaspect.php
>
> Just try that with some old-fashioned analog system.
>
When I tune around the shortwave bands, I hear speech of many
languages. And music.
>
> "There is a global trend towards the adoption of digital technology in radio
> and communications, especially for distribution and transmission. "
>
> And:
>
> "However, the limited fidelity of existing AM services is causinglisteners
> to search for other alternatives."
>
> http://drm.org/system/whydigital.php
Anyone who so much as picks up an AM radio is after something other
than audio fidelity. That's the nature of the beast, and everyone knows
it.
>
> Well, I'm confused on this point. Didn't AM became obselete in the forties
> with the introduction of FM? If I remember my history correctly, didn't all
> the limited fidelity AM stations go bankrupt as all their listeners were
> drawn to high fidelity FM?
>
> It seems limited fidelity AM is in for it again:
>
> "DRM is the only universal, non-proprietary digital AM radio system with
> near-FM quality sound available to markets worldwide."
>
>
> There ya have it. DRM has both "near-FM quality sound" and digital
> trendiness.
>
> I can't think of any better reasons for the listener to care.
>
> Frank Dresser
These are the things that SW listeners care least about. If this is the
primary appeal of DRM, it is thoroughly and completely doomed.
Steve
sdan...@nyc.rr.com
will bring back the typewriter. This new technology will allegedly turn
a typewriter into a 'near PC quality' word processor.
cuh...@webtv.net
typeriters you see at the thriftstores for a few dollars,you can sell
them to Mexico and other third world countries,they still use them.
cuhulin
Telamon
Kristoff Bonne <compaq...@kristoff.bonne> wrote:
> Gegroet,
>
>
> Telamon schreef:
> >>For One and All, ABOUT - Digital Radio Mondiale (DRM) DRM =>
> >>http://www.drm.org/.
>
> > ALL you need to know is that the implementation was screwed up and
> > over hyped. OH YEAH and it was lied about a lot buy the DRM
> > organization. AND it takes up more bandwidth than it was supposed
> > too. BUT it is just another system than the current analog with its
> > mixed bag of pluses and minuses, which make it no better than the
> > current analog system so why change to it?
>
> Aren't you mixing up DRM with IBOC-AM?
Nope. I'm talking about Deception Radio Mondiale.
> DRM might bring people back to LW/MW/SW and they might not even know
> it.
LW and MW are around 24/7 but SW stations change frequencies all
the time. It takes a little more effort to find a SW station.
> One of the things with DRM (and especially with the DAB/DRM chipset
> now available) is that the user will just be presented with a list of
> stations and he will just have to pick the one from the list. She
> will not know if she is listening to a DAB broadcast at 1.4 Ghz or
> long-wave at below 200 Khz.
Most women are clueless about technology but what about us guys?
But seriously what station is going to broadcast the whole SW station
schedule in the background data stream. Do you have any idea how big
that is? You would need to do this because schedules (times and
frequencies) change all the time.
> DRM has two major advantages: - it does away with fading, which is
> one of the things people find most annoying about LW/MW/SW. The
> "audio-quality" aspect is a bit mood as it all depends on what mode
> you are using and I think for most people is not the most important
> element. But if you produce a stable signal without fading, this
> would make LW/MW/SW broadcasts quite acceptable by most people.
1. Fading
a. Fading is replaced with dropouts. I fail to understand how that can
even be considered an improvement.
b. I don't find it the most annoying thing.
c. Analog has sync detection, which eliminates most of the fading most
of the time. This is much better than drop outs.
2. Audio quality.
a. I have several analog radios that during real SW reception sound much
better than the audio demonstration files on the DRM website.
b. An analog radio with sync detection would sound better than a DRM
radio using the same radio spectrum bandwidth.
c. No LW broadcast in NA but I find that MW and SW are quite acceptable.
> (The term "near-FM" is marketing talk, just ignore it).
No I won't ignore it. The better sound quality hype is just another
example of the sales deception that surrounds the DRM technology.
> It allows broadcasters to break into certain markets by broadcasting
> from abroad. BCE (RTL's broadcasting arm) plan to use it to broadcast
> using DRM on LW, MW and SW towards different countries.
I don't know about this. What exactly does the DRM technology have to do
with enabling markets?
> The new frequencies on LW and MW they have requested at the ITU are
> 279 Khz (Junglinster towards Germany), 567 Khz (Clervoux towards the
> Netherlands), 783 Khz (Beidweiler towards France) and 1098 Khz
> (Clervoux towards Belgium).
I'm happy this is not in my part of the world.
> For SW, they have asked the HFCC for coordination for two
> frequencies: 5990 and 6095 Khz.
I would prefer that the DRM transmissions stay out of the international
broadcast bands and stick to the digital utility frequencies.
--
Telamon
Ventura, California
Kristoff Bonne
Frank Dresser schreef:
>>Quite a lot of shortwave station broadcast at more then one frequency at
>>a time so it possible to have a radio tuned to two frequencies at the
>>same time and let the radio "interleave" the signals from two sources
>>when one of the has a drop-out.
>>(DRM includes "alternative frequency" information, so the receiver is
>>able to find out these additional signals by itself).
> That's diversity reception. Diversity reception is almost as old as SW
> radio, but it never has been popular with the public. ...
True, because it can only when the two antenna's are far enough appart
(wavelengh-wize), like on a car. On a portable device, it does not make
that much sence.
But when you apply this technology in different frequencies, you can
apply it with a single antenna.
Also note that in theory, using digital technology, you can add a
time-offset between the two signals so that -if both signals fall away,
you can hope to get a signal from the 2nd (delayed) signal by the time
fadding has gone.
Both US satellite-radio systems have a time-offset between the signals
from their satellites. (something like 3 seconds, IIRC); but it would be
nice to test how much this would help on shortwave. My guess is that it
would if you use transmissions on two signals close together as the
fading for both signals will happen at almost the same time).
> ... I can imagine
> diversity reception would be easier to do digitially, but diversity
> reception doesn't always help. There will be moments in which propagation
> will be bad on all frequencies, and longer times, such as during solar flare
> events, in which SW will be useless.
True.
>>We will see. If DRM works well for most of the time and additional
>>stations have interesting content, people will get one of these
>>"RTL-radios" (which will happen to be a DRM-radio and which happens to
>>work on shortwave-frequencies).
> SW radio works well most of the time, at least in the target areas. Let's
> say a target area gets good reception 95% of the time. How much more
> reliable might the reception be with DRM? 98%? 99%? Will 99% reliable
> reception be good enough for non-hobbyists? I really don't think so.
I don't know. That' a marketing descision.
My main issue is that SW will stop working in most cases when you take
your radio inside the house or when somebody switches on a device that
creates that much QRM.
We will see.
>>For RTL, the reason is pretty simple. They see that people are moving
>>away from MW and LW to FM just because FM sounds that much better.
>>But getting a FM-licence for just a new radio-station is not that
>>simple. (you are dependent of the policy of every country involved).
(...)
> Won't the European Union standardize some of these bureaucratic problems?
This is not a juristicion of the EU. "Culture" is a national (and in
most cases regional) issue.
The only thing the EU can say is that say you write out a competition
for new FM-licences that you must treath foreign companies the same way
as companies from your own country.
> Is there really much advantage to having one transmitter covering a huge
> area? In the US, stations are individualized to the extent that they
> usually carry the news, traffic and weather for their local market.
In most European countries, there is a mix of a number of "national"
radio-stations and a number of "local" radio-stations.
Sometimes, there are "localised" national radio-stations who are
national stations broadcasting exactly the same signal for 99 % of the
time, and only have a "local" signal for (say) 3 times 5 minutes a day.
(but they are marketed as a national radio-station).
Anycase, as any other digital broadcasting-system, DRM allows for
broadcasting of "local" content over a national infrastructure; e.g. by
using datacasting to broadcast the local content "on the side" and
"insert" these audio-segments into the main broadcasting-stream when it
is needed.
(A bit like sirius -or was it XM?- wants to do. -OK, it least, they have
a patent for this).
>>We will see, but as DMR is a digital broadcasting-system, you can expect
>>additional improvements in the receivers too.
> The performance of analog radios could have been improved, if people wanted
> to pay for the improvements. The real improvements in analog radios over
> the last few years has been in price.
True.
But the point I wanted to make is that the DRM spec is now out there and
the real life transmissions have just started.
But what we will see next is that advanced transmissions- and
receptions-techniques to start to be applied which will take it all to a
next step.
Kristoff Bonne
Frank Dresser schreef:
> It's worth remembering all the commercial SW data and phone links which were
> in use before the satellite era. They had diversity reception,
> sophisticated (for the time) digital modes, high power transmitters, high
> gain antennas, etc. Yet they abandoned their large investment in SW as
> satellites became available. Even with all their technology, SW still
> wasn't reliable enough.
I agree.
> I think the average person expects at least the same order of reliablity
> from their radios.
Well, there was advertisement video-clip on the website of RTL some time
ago, which put it this way.
"OK, it's nice to listen to your favourate RTL station at home and in
the car here in Germany; but what when you are on the beach in sunny
spain during your summer-break? Well, using DRM, you will now be able to
take your well-know RTL-station with you even when you are partying away
in Ibiza".
(OK, something like that).
Perhaps DRM over SW will not provide 100 % garanteed reception, but for
this kind of service, it may be sufficient good.
Anycase, we will see.
But concidering the fact that BCE have asked for two HF-frequencies for
DRM, it looks that they are planning on trying it!
Frank Dresser
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
>>
> True, because it can only when the two antenna's are far enough appart
> (wavelengh-wize), like on a car. On a portable device, it does not make
> that much sence.
>
> But when you apply this technology in different frequencies, you can
> apply it with a single antenna.
There's different kinds of diversity reception. Antenna diversity reception
involves two or more antennas seperated by a distance of a few wavelengths
or more. Polorization diversity reception uses antennas whose polorization
is at right angles to one another. Frequency diversity uses different
frequencies. At least that's the types of diversity reception listed in my
copy of "The Radio Engineer's Handbook" (copyright 1943). None of these
concepts were presented as anything new at the time. I think the
Hallicrafters Double Diversity Receiver was capable of all three kinds of
diversity reception with the right antennas. The DDR was sold -- well, was
offered, as very few were sold -- to the public in the late 30s.
>
> Also note that in theory, using digital technology, you can add a
> time-offset between the two signals so that -if both signals fall away,
> you can hope to get a signal from the 2nd (delayed) signal by the time
> fadding has gone.
Right. I suppose that could be called time diversity reception, although I
don't think anybody uses that term.
>
> Both US satellite-radio systems have a time-offset between the signals
> from their satellites. (something like 3 seconds, IIRC); but it would be
> nice to test how much this would help on shortwave. My guess is that it
> would if you use transmissions on two signals close together as the
> fading for both signals will happen at almost the same time).
Does DRM allow a time delay stream? I'd think such a system would be more
attactive for most people, rather than a single higher fidelity stream.
>
> My main issue is that SW will stop working in most cases when you take
> your radio inside the house or when somebody switches on a device that
> creates that much QRM.
>
> We will see.
>
[snip]
> In most European countries, there is a mix of a number of "national"
> radio-stations and a number of "local" radio-stations.
>
> Sometimes, there are "localised" national radio-stations who are
> national stations broadcasting exactly the same signal for 99 % of the
> time, and only have a "local" signal for (say) 3 times 5 minutes a day.
> (but they are marketed as a national radio-station).
>
>
>
> Anycase, as any other digital broadcasting-system, DRM allows for
> broadcasting of "local" content over a national infrastructure; e.g. by
> using datacasting to broadcast the local content "on the side" and
> "insert" these audio-segments into the main broadcasting-stream when it
> is needed.
> (A bit like sirius -or was it XM?- wants to do. -OK, it least, they have
> a patent for this).
That sounds a bit like what the US radio networks do. They provide blocks
of programming, and the local stations get sections of time to insert their
own programming.
>
> But the point I wanted to make is that the DRM spec is now out there and
> the real life transmissions have just started.
>
> But what we will see next is that advanced transmissions- and
> receptions-techniques to start to be applied which will take it all to a
> next step.
Yes, but as you suggested, this comes down to marketing. If DRM doesn't
fufill people's expection of what radio ought to be, then the next step will
be the next false start.
Frank Dresser
cuh...@webtv.net
cuhulin
Kristoff Bonne
Frank Dresser schreef:
>>True, because it can only when the two antenna's are far enough appart
>>(wavelengh-wize), like on a car. On a portable device, it does not make
>>that much sence.
>>But when you apply this technology in different frequencies, you can
>>apply it with a single antenna.
> There's different kinds of diversity reception. Antenna diversity reception
> involves two or more antennas seperated by a distance of a few wavelengths
(...)
> diversity reception with the right antennas. The DDR was sold -- well, was
> offered, as very few were sold -- to the public in the late 30s.
Interesting. Thanks.
Well, one of the things about technology is that sometimes "textbook
technology" which has existed for long only in books or in very
specialised applications (usually defence) just becomes mainstream. Take
COFDM or CDMA.
I was reading an small article on the VCT (Voice Channel Telegraphy)
technologies, and overthere they use time-diversity and frequency
diversity too.
They put the same telegraphy-signal multiple times into the same
VCT-channel, put all with a different time-offset.
>>Both US satellite-radio systems have a time-offset between the signals
>>from their satellites. (something like 3 seconds, IIRC); but it would be
>>nice to test how much this would help on shortwave. My guess is that it
>>would if you use transmissions on two signals close together as the
>>fading for both signals will happen at almost the same time).
> Does DRM allow a time delay stream? I'd think such a system would be more
> attactive for most people, rather than a single higher fidelity stream.
In theory, every digital signal allows for time-diversity on the
condition that the signal on both channels in exactly the same.
So, if you build it into a receiver, then yes, you can do this.
DRM puts a identification-tag on every stream (which is shared with DAB,
FM/RDS and probably also the upcoming RDS-over-AM standard so it allows
receivers to switch between the different broadcasting-channel) and the
"AF" (alternative frequency) information allows for the receiver to find
the additional streams.
AFAIK, there is no indication of a stream is delayed or not, but that's
something the receiver can find out by himself.
Now, I don't think there is anything in the specs for a situation where
you would put the same signal twice inside the same DRM transport-stream
(one delayed to the other) and give them both the same streamid, so I
don't know how a receiver would react to that. (some of them will
probably crash :-) )
Perhaps that's something to add in the specs.
>>Anycase, as any other digital broadcasting-system, DRM allows for
>>broadcasting of "local" content over a national infrastructure; e.g. by
>>using datacasting to broadcast the local content "on the side" and
>>"insert" these audio-segments into the main broadcasting-stream when it
>>is needed.
>>(A bit like sirius -or was it XM?- wants to do. -OK, it least, they have
>>a patent for this).
> That sounds a bit like what the US radio networks do. They provide blocks
> of programming, and the local stations get sections of time to insert their
> own programming.
True, with the difference that in the US-system, the individual
radio-stations are all different legal entities by themselfs.
Overhere, there only is a single legal entity and when there are no
local broadcasts, all transmittors transmit exactly the same signal.
(which is why using FM/RDS "AF" and these networks of transmittors, you
can drive from one side of the country to the other side and keep tuned
to the same radio-station.
>>But the point I wanted to make is that the DRM spec is now out there and
>>the real life transmissions have just started.
>>But what we will see next is that advanced transmissions- and
>>receptions-techniques to start to be applied which will take it all to a
>>next step.
> Yes, but as you suggested, this comes down to marketing. If DRM doesn't
> fufill people's expection of what radio ought to be, then the next step will
> be the next false start.
True. My personal opinion is that -concidering the interest of quite a
lot of the big broadcasters- it will succeed, but we will see.
Kristoff Bonne
Oeps. I am a bit behind scedule replying to this one.
Telamon schreef:
> Nope. I'm talking about Deception Radio Mondiale.
Didn't know this one. :-)
Nice!!!
>>DRM might bring people back to LW/MW/SW and they might not even know
>>it.
> LW and MW are around 24/7 but SW stations change frequencies all
> the time. It takes a little more effort to find a SW station.
That's what "AF" is for. (Alternative Frequency information inserted
into the DRM stream, just like on FM/RDS).
>>One of the things with DRM (and especially with the DAB/DRM chipset
>>now available) is that the user will just be presented with a list of
>>stations and he will just have to pick the one from the list. She
>>will not know if she is listening to a DAB broadcast at 1.4 Ghz or
>>long-wave at below 200 Khz.
> Most women are clueless about technology but what about us guys?
Great. Do I write "she" to say "hey, let's not be sexist and say that
only men know about technology and radio", and you reply "women don't
know anything about radio".
:-)
> But seriously what station is going to broadcast the whole SW station
> schedule in the background data stream. Do you have any idea how big
> that is? You would need to do this because schedules (times and
> frequencies) change all the time.
First of all, that's not such a big issue, as there do exist things like
the "EPG". It broadcasting-technology neutral so it can be used in
DAB, DVB and DRM.
Second, the only thing the radio will do is scan all frequencies it can
receive and compose a list based on that. That's how DAB radios work
nowdays too.
>>DRM has two major advantages: - it does away with fading, which is
>>one of the things people find most annoying about LW/MW/SW. The
>>"audio-quality" aspect is a bit mood as it all depends on what mode
>>you are using and I think for most people is not the most important
>>element. But if you produce a stable signal without fading, this
>>would make LW/MW/SW broadcasts quite acceptable by most people.
> 1. Fading
> a. Fading is replaced with dropouts. I fail to understand how that can
> even be considered an improvement.
Only if the signal goes below a certain S/N threshold.
> b. I don't find it the most annoying thing.
Well, last year I was in Northern Italy and I was listening to the
worldservice of the public broadcaster of Flanders (dutch-speaking
belgium) on shortwave; and -to be honest- my wife was pretty anoyed by
the fading-element.
Somebody who just "hears" a radio (so, who is not really "listening") is
used to have a radio with a more-or-less constant quality-signal. They
are not really used to have a radio sound good, then get all kind of
noice, then sound good again, and then with noice again.
It attacks their attention and this annoys them. Radio should be a
"background noice" thing and this means that is should be more-or-less
constant.
> c. Analog has sync detection, which eliminates most of the fading most
> of the time. This is much better than drop outs.
AFAIK, sync detection is against partial-cochannel interference, not
against fading.
> 2. Audio quality.
> a. I have several analog radios that during real SW reception sound much
> better than the audio demonstration files on the DRM website.
True, but there are stations who also sound worse.
> b. An analog radio with sync detection would sound better than a DRM
> radio using the same radio spectrum bandwidth.
Do you actually have a DRM-radio? Can you compair?
> c. No LW broadcast in NA ...
Correct, but I read somewhere that Australia is thinking of restarting
broadcasts on LW (because of DRM).
Most NDBs have disappeared from that band overthere.
> ... but I find that MW and SW are quite acceptable.
Are there domestic SW-broadcasts in the NA? CBC/RC?
>>(The term "near-FM" is marketing talk, just ignore it).
> No I won't ignore it. The better sound quality hype is just another
> example of the sales deception that surrounds the DRM technology.
No, I meant that the term "near FM" is just marketing-talk. It allows
for better audio then AM, that is for sure but it all depends on what
mode you use.
If you listen to a very-low bitrate auxilairy channel (e.g. one used for
broadcasting traffic-messages) it will sound much worse then FM.
If you use it in the 20 KHz mode in the 11 meter broadcasting-band, it
will probably sound better then FM.
The audio-quality-issue is technically much more complex then this, but
-marketing-wize- "near FM" is probably the simplest thing to say.
>>It allows broadcasters to break into certain markets by broadcasting
>>from abroad. BCE (RTL's broadcasting arm) plan to use it to broadcast
>>using DRM on LW, MW and SW towards different countries.
> I don't know about this. What exactly does the DRM technology have to do
> with enabling markets?
It allows them to broadcast with a "accepable" signal across the borders
so that -using their Luxembourg license- they can "break into" other
markets.
>>The new frequencies on LW and MW they have requested at the ITU are
>>279 Khz (Junglinster towards Germany), 567 Khz (Clervoux towards the
>>Netherlands), 783 Khz (Beidweiler towards France) and 1098 Khz
>>(Clervoux towards Belgium).
> I'm happy this is not in my part of the world.
Why not. The more channels, the better.
Anycase, the biggest user of DRM will probably be not in Europe, but
will be in China. (for a very different reason, but that's a different
discussion).
>>For SW, they have asked the HFCC for coordination for two
>>frequencies: 5990 and 6095 Khz.
> I would prefer that the DRM transmissions stay out of the international
> broadcast bands and stick to the digital utility frequencies.
Why is that. If they are general-public broadcasts, that's where they
belong, isn't it?
What does a x. KW high-power general-public broadcasting-station do in
the same band as medium-power utility-broadcasts?
If these broadcasts are analog or digital are IMHO of no importance.
Cheerio! Kr. Bonne.
sdan...@nyc.rr.com
that was behind its time, meaning it would have been successful 50
years ago, but is an anachronism today. It's neat that there are still
some DRM broadcasts around, but don't count on that to continue. In
particular, don't sink a lot of money into a DRM-capable receiver.
Steve
RHF
So in 2015 we can then judge whether DRM may
indeed be the norm and an accepted form of
Shortwave Broadcasting or some idea that
never went anywhere over time. ~ RHF
.
.
. .
sdan...@nyc.rr.com
more thing that renders DRM obsolete. The writing is already on the
wall.
Frank Dresser
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
>
>
> Well, one of the things about technology is that sometimes "textbook
> technology" which has existed for long only in books or in very
> specialised applications (usually defence) just becomes mainstream. Take
> COFDM or CDMA.
>
In the US, much of the pioneering work was done by commercial interests such
as RCA and AT&T. There was good money to be made trafficing messages around
the world!
>
[snip]
>
> Now, I don't think there is anything in the specs for a situation where
> you would put the same signal twice inside the same DRM transport-stream
> (one delayed to the other) and give them both the same streamid, so I
> don't know how a receiver would react to that. (some of them will
> probably crash :-) )
>
>
> Perhaps that's something to add in the specs.
But wouldn't a new radio crashing DRM spec make at least some of the new DRM
radios at least partially obselete? If so, that's bad marketing. Once the
radios start selling, they're pretty much stuck with whatever works with all
the DRM radios.
[snip]
> True. My personal opinion is that -concidering the interest of quite a
> lot of the big broadcasters- it will succeed, but we will see.
>
>
The real decision will be made by the public. In the US, the broadcasters
had a great amount of enthusisiam for AM stereo. There were some radios
offered, but, for the most part, the public didn't care. AM stereo just
never caught on, for whatever reason.
I suppose it's possible that DRM may also be an incomplete success. For
example, the public might find the occasional SW dropouts too annoying, but
they might very much like the improved signal to noise ratio on LW.
Frank Dresser
Tom Holden
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
>> c. Analog has sync detection, which eliminates most of the fading most of
>> the time. This is much better than drop outs.
>
>
> AFAIK, sync detection is against partial-cochannel interference, not
> against fading.
Perhaps its greatest benefit is improved immunity from distortion due to
selective fading, especially that which sucks out the carrier. Suppressing
one sideband also reduces fading distortion. The Dream software DRM decoder
also incorporates a synchronous AM, selectable sideband detector. The
improvement in listenability for a DSB AM signal in the presence of
selective fading is truly remarkable when it is used in synchronous ECSS
mode.
Broadcasters would free spectrum, reduce interference, be more energy
efficient, maintain compatability with the huge installed base of AM radios
by converting to SSBc mode. Radios manufactured with DSP capable of
synchronous AM selectable sideband would probably require less silicon than
DRM (read cheaper), be more energy efficient (read eat batteries more
slowly), be compatable with the huge installed base of DSBAM transmitters
and the then-growing number of SSBc transmitters. Why don't we hear more
about this alternative from broadcasters and manufacturers? Have I missed
something?
>> b. An analog radio with sync detection would sound better than a DRM
>> radio using the same radio spectrum bandwidth.
>
> Do you actually have a DRM-radio? Can you compair?
While DRM might give the subjective impression of wider frequency response
and higher signal-to-noise ratio, to fit within a 10 or 20 kHz bandwidth, it
necessarily uses a very low bitrate lossy codec. I find that listening to
such codecs is aggravating, moreso than (and very different from) the
dynamic changes in spectral balance from an AM transmission in moderate
fades.
Moreover, the DRM spectrum is rectangular - even energy distribution. If we
take our 10 kHz channel and use SSBc to fill it (carrier at channel edge),
we will get nearly 10 kHz audio bandwidth. If we also use pre-emphasis (as
is done in FM), or one of the (ancient) Dolby or dBx type noise reduction
systems to lift the treble energy in the sideband, we will get a much
improved S/N. Still very listenable on a conventional DSBAM radio with
typical IF and AF passbands.
Why don't we hear about this approach? It sounds so easy I think I should
build a transmitter and experiment with it! There must be a catch...
Tom
Telamon
Kristoff Bonne <compaq...@kristoff.bonne> wrote:
> Gegroet,
>
>
> Oeps. I am a bit behind scedule replying to this one.
No problem.
> Telamon schreef:
> > Nope. I'm talking about Deception Radio Mondiale.
> Didn't know this one. :-)
>
> Nice!!!
You know why it's nice? Because it true.
> >>DRM might bring people back to LW/MW/SW and they might not even know
> >>it.
> > LW and MW are around 24/7 but SW stations change frequencies all
> > the time. It takes a little more effort to find a SW station.
>
> That's what "AF" is for. (Alternative Frequency information inserted
> into the DRM stream, just like on FM/RDS).
The problem is that you have to get a decent signal to get the
information.
> >>One of the things with DRM (and especially with the DAB/DRM chipset
> >>now available) is that the user will just be presented with a list of
> >>stations and he will just have to pick the one from the list. She
> >>will not know if she is listening to a DAB broadcast at 1.4 Ghz or
> >>long-wave at below 200 Khz.
>
> > Most women are clueless about technology but what about us guys?
>
> Great. Do I write "she" to say "hey, let's not be sexist and say that
> only men know about technology and radio", and you reply "women don't
> know anything about radio".
> :-)
You could have written the same thing without he or she. Why bring sex
into it.
> > But seriously what station is going to broadcast the whole SW station
> > schedule in the background data stream. Do you have any idea how big
> > that is? You would need to do this because schedules (times and
> > frequencies) change all the time.
>
> First of all, that's not such a big issue, as there do exist things like
> the "EPG". It broadcasting-technology neutral so it can be used in
> DAB, DVB and DRM.
What is "EPG"? If it's another digital stream then you have to able to
pick up the signal to get the information and that is a lot of
information for a low bit rate signal that can, lets face it, have drop
outs.
> Second, the only thing the radio will do is scan all frequencies it can
> receive and compose a list based on that. That's how DAB radios work
> nowdays too.
I can do that right now so who needs DRM?
> >>DRM has two major advantages: - it does away with fading, which is
> >>one of the things people find most annoying about LW/MW/SW. The
> >>"audio-quality" aspect is a bit mood as it all depends on what mode
> >>you are using and I think for most people is not the most important
> >>element. But if you produce a stable signal without fading, this
> >>would make LW/MW/SW broadcasts quite acceptable by most people.
>
> > 1. Fading
> > a. Fading is replaced with dropouts. I fail to understand how that can
> > even be considered an improvement.
> Only if the signal goes below a certain S/N threshold.
Which it will.
> > b. I don't find it the most annoying thing.
>
> Well, last year I was in Northern Italy and I was listening to the
> worldservice of the public broadcaster of Flanders (dutch-speaking
> belgium) on shortwave; and -to be honest- my wife was pretty anoyed by
> the fading-element.
>
>
> Somebody who just "hears" a radio (so, who is not really "listening") is
> used to have a radio with a more-or-less constant quality-signal. They
> are not really used to have a radio sound good, then get all kind of
> noice, then sound good again, and then with noice again.
>
> It attacks their attention and this annoys them. Radio should be a
> "background noice" thing and this means that is should be more-or-less
> constant.
It looks to me that you have not used a good analog radio with sync
detection and an adjustable AGC. With those two functions at your
disposal you won't have that problem.
> > c. Analog has sync detection, which eliminates most of the fading most
> > of the time. This is much better than drop outs.
>
>
> AFAIK, sync detection is against partial-cochannel interference, not
> against fading.
This tells me that you have never used a radio with sync detection. A
sync detector helps with selective fading and a good one will give weak
signals a boost. This together with a properly adjusted AGC will give
you constant quality audio.
> > 2. Audio quality.
> > a. I have several analog radios that during real SW reception sound much
> > better than the audio demonstration files on the DRM website.
>
> True, but there are stations who also sound worse.
So what that got to do with it. The DRM "sound" sucks with a good signal
and analog station with a good signal sounds much better. A DRM signal
that was weak would be dropping out and would get turned off.
> > b. An analog radio with sync detection would sound better than a DRM
> > radio using the same radio spectrum bandwidth.
>
> Do you actually have a DRM-radio? Can you compair?
No I don't. I told you I listened to the samples on the DRM website and
besides that there are plenty of examples on the web of low bit rate
audio encoded files that don't sound very good.
> > c. No LW broadcast in NA ...
> Correct, but I read somewhere that Australia is thinking of restarting
> broadcasts on LW (because of DRM).
>
> Most NDBs have disappeared from that band overthere.
>
>
> > ... but I find that MW and SW are quite acceptable.
> Are there domestic SW-broadcasts in the NA? CBC/RC?
Yes there are quite a few SW broadcasters and broadcast sites in NA but
I spend little time listening to them.
> >>(The term "near-FM" is marketing talk, just ignore it).
>
> > No I won't ignore it. The better sound quality hype is just another
> > example of the sales deception that surrounds the DRM technology.
>
> No, I meant that the term "near FM" is just marketing-talk. It allows
> for better audio then AM, that is for sure but it all depends on what
> mode you use.
I know what you meant. You are missing my point that this is not the
extent of the hype and I strongly disagree that DRM sounds better than
analog AM. It clearly sounds worse. You would have to increase the
bandwidth DRM currently uses for it to sound better.
> If you listen to a very-low bitrate auxilairy channel (e.g. one used for
> broadcasting traffic-messages) it will sound much worse then FM.
> If you use it in the 20 KHz mode in the 11 meter broadcasting-band, it
> will probably sound better then FM.
And just how do you think analog would sound using the same bandwidth?
> The audio-quality-issue is technically much more complex then this, but
> -marketing-wize- "near FM" is probably the simplest thing to say.
>
>
> >>It allows broadcasters to break into certain markets by broadcasting
> >>from abroad. BCE (RTL's broadcasting arm) plan to use it to broadcast
> >>using DRM on LW, MW and SW towards different countries.
>
> > I don't know about this. What exactly does the DRM technology have to do
> > with enabling markets?
>
> It allows them to broadcast with a "accepable" signal across the borders
> so that -using their Luxembourg license- they can "break into" other
> markets.
So your argument for DRM here is change the technology to overcome a
political problem?
> >>The new frequencies on LW and MW they have requested at the ITU are
> >>279 Khz (Junglinster towards Germany), 567 Khz (Clervoux towards the
> >>Netherlands), 783 Khz (Beidweiler towards France) and 1098 Khz
> >>(Clervoux towards Belgium).
>
> > I'm happy this is not in my part of the world.
>
> Why not. The more channels, the better.
Just the opposite. One low bit rate crappie sounding DRM signal wastes
three channels. A good sounding DRM signal would waste twice as many.
> Anycase, the biggest user of DRM will probably be not in Europe, but
> will be in China. (for a very different reason, but that's a different
> discussion).
Actually besides sounding like crap DRM biggest problem is that
broadcasters can start controlling who can listen. DRM would also be
easier to jam. Small wonder China would go for it.
> >>For SW, they have asked the HFCC for coordination for two
> >>frequencies: 5990 and 6095 Khz.
> > I would prefer that the DRM transmissions stay out of the international
> > broadcast bands and stick to the digital utility frequencies.
>
> Why is that. If they are general-public broadcasts, that's where they
> belong, isn't it?
No they are a digital mode that interferes with the analog signals I
want to listen too. They should stick to the part of the spectrum for
digital mode signals.
> What does a x. KW high-power general-public broadcasting-station do in
> the same band as medium-power utility-broadcasts?
Why should a digital mode signal be sitting in the middle of a analog AM
broadcast band?
> If these broadcasts are analog or digital are IMHO of no importance.
I don't know why you would say this. Usage and mode of transmission
determine what frequency you transmit on. Why should DRM be an exception?
> Cheerio! Kr. Bonne.
Yeah, cheerio to you too.
--
Telamon
Ventura, California
Mark Zenier
Huh? You're holding the funeral before the damn thing is even born.
Consumer grade receivers are just coming on the market in Europe now.
But, on the other hand, if whoever it was operates on 6095 at the
same time as I'm trying to get Radio New Zealand in the morning...
Mark Zenier mze...@eskimo.com
Googleproofaddress(account:mzenier provider:eskimo domain:com)
Kristoff Bonne
Telamon schreef:
>>Oeps. I am a bit behind scedule replying to this one.
> No problem.
OK. I'll take your message first this time.
>>>Nope. I'm talking about Deception Radio Mondiale.
>>Didn't know this one. :-)
>>Nice!!!
> You know why it's nice? Because it true.
To be honest, I was refering to the "word-game". :-)
>>>LW and MW are around 24/7 but SW stations change frequencies all
>>>the time. It takes a little more effort to find a SW station.
>>That's what "AF" is for. (Alternative Frequency information inserted
>>into the DRM stream, just like on FM/RDS).
> The problem is that you have to get a decent signal to get the
> information.
Once a radio has tuned to a stream and received one valid "SI" frame, it
has all the information about all possible frequencies the broadcaster
uses. The set will store that information so that -the next time you
switch your set to a certain program- the radio knows what frequencies
to look at.
>>>>One of the things with DRM (and especially with the DAB/DRM chipset
>>>>now available) is that the user will just be presented with a list of
>>>>stations and he will just have to pick the one from the list. She
>>>>will not know if she is listening to a DAB broadcast at 1.4 Ghz or
>>>>long-wave at below 200 Khz.
>>>Most women are clueless about technology but what about us guys?
>>Great. Do I write "she" to say "hey, let's not be sexist and say that
>>only men know about technology and radio", and you reply "women don't
>>know anything about radio".
>>:-)
> You could have written the same thing without he or she. Why bring sex
> into it.
If you write something sex-neutral, why use "he"? Half of the population
is female.
>>First of all, that's not such a big issue, as there do exist things like
>> the "EPG". It broadcasting-technology neutral so it can be used in
>>DAB, DVB and DRM.
> What is "EPG"? If it's another digital stream then you have to able to
> pick up the signal to get the information and that is a lot of
> information for a low bit rate signal that can, lets face it, have drop
> outs.
The EPG ('Electronic Program Guide') can be broadcaste as a seperate
audio-stream (as usually is done on DAB) but can also be broadcasted as
a PAD-stream (PAD = Program Associated Data)
PAD data in inserted into the few spare bits at the end of each
audio-packet which are not used (because of the way the MPEG-format
encoding is done, you cannot really fillup the frames upto the last byte).
>>Second, the only thing the radio will do is scan all frequencies it can
>>receive and compose a list based on that. That's how DAB radios work
>>nowdays too.
> I can do that right now so who needs DRM?
Sure, but AM does not provide an identification of the stations. This
means that DRM can provide a list of station-names (and not just
frequencies) and remove the doubles from it.
And because of the AF-information, a DRM-set will still be able to tune
to a station in that list, even it has already switched to a different
frequency.
The EPG-information inside the stream will then also tell you what
program you are listing to, what it is about and when the next programs
starts and what that will be about.
>>>>DRM has two major advantages: - it does away with fading, which is
>>>>one of the things people find most annoying about LW/MW/SW. The
>>>>"audio-quality" aspect is a bit mood as it all depends on what mode
>>>>you are using and I think for most people is not the most important
>>>>element. But if you produce a stable signal without fading, this
>>>>would make LW/MW/SW broadcasts quite acceptable by most people.
>>>1. Fading
>>>a. Fading is replaced with dropouts. I fail to understand how that can
>>>even be considered an improvement.
>>Only if the signal goes below a certain S/N threshold.
> Which it will.
True, but at that time analog reception will be impossible too.
So, the question is how bad does your signal have to get to result in
drop-outs and would an analog signal still be acceptable at that point.
Anycase, as I already said in my message-thread with Frank, DRM allows
for a number techniques which can be used to reduce the fading on
shortwave which are impossible or much more difficult on analog
broadcasting.
>>It attacks their attention and this annoys them. Radio should be a
>>"background noice" thing and this means that is should be more-or-less
>>constant.
> It looks to me that you have not used a good analog radio with sync
> detection and an adjustable AGC.
It was a hitachi KGWS1 (a combined SW/worldspace radio).
> With those two functions at your
> disposal you won't have that problem.
How much radio-sets do have this functionality?
Concider somebody who just buys a SW-radio to listen to the daily news
from home when you're on holiday in one of the costa's, how many of this
kind of radio-statons have this?
Not a lot I would say, or else all SW-broadcasters would have switched
to SSB.
>>>2. Audio quality.
>>>a. I have several analog radios that during real SW reception sound much
>>>better than the audio demonstration files on the DRM website.
>>True, but there are stations who also sound worse.
> So what that got to do with it. The DRM "sound" sucks with a good signal
> and analog station with a good signal sounds much better. A DRM signal
> that was weak would be dropping out and would get turned off.
OK. Let's take the examples on the DRM-website. They had bad
audio-quality and good DRM-quality.
(but that's what you would expect on DRM, wouldn't you? :-)))
To make an honest comparison, you should make a comparison between a
live DRM-broadcast and the same content, on a "average" SW-radio (hence,
no SSB, no sync-detection, ...) as that is the equipement people who are
targeted by this technology.
This is something that we can do ourselfs once DRM-receivers are widely
available and not be dependent on audio-samples of websites of other people.
>>>... but I find that MW and SW are quite acceptable.
>>Are there domestic SW-broadcasts in the NA? CBC/RC?
> Yes there are quite a few SW broadcasters and broadcast sites in NA but
> I spend little time listening to them.
OK, but do they target a NA-audience?
I guess there's RCI who's targetting the US and visa-versa. But does
CBC/RC use shortwave for their domestic service?
>>>>(The term "near-FM" is marketing talk, just ignore it).
>>>No I won't ignore it. The better sound quality hype is just another
>>>example of the sales deception that surrounds the DRM technology.
>>No, I meant that the term "near FM" is just marketing-talk. It allows
>>for better audio then AM, that is for sure but it all depends on what
>>mode you use.
> I know what you meant. You are missing my point that this is not the
> extent of the hype and I strongly disagree that DRM sounds better than
> analog AM. It clearly sounds worse. You would have to increase the
> bandwidth DRM currently uses for it to sound better.
Wait, are you telling me that a good DRM-signal in 10 Khz sounds (e.g.
in stereo) sounds worse then the same signal in AM?
Do you have audio-samples to support this claim?
>>If you listen to a very-low bitrate auxilairy channel (e.g. one used for
>>broadcasting traffic-messages) it will sound much worse then FM.
>>If you use it in the 20 KHz mode in the 11 meter broadcasting-band, it
>>will probably sound better then FM.
> And just how do you think analog would sound using the same bandwidth?
I don't know. It would be nice to test.
However, the main reason why broadcasters are interested in 20 Khz DRM
is a path for the digitalisation of the local radio-stations now on FM.
DRM is partically interesting as it allows for SFNs and a mini-SFN by 2
or 3 transmittors around the city allows you to lower the total
transmission-power quite dramastically.
>>>I don't know about this. What exactly does the DRM technology have to do
>>>with enabling markets?
>>It allows them to broadcast with a "accepable" signal across the borders
>>so that -using their Luxembourg license- they can "break into" other
>>markets.
> So your argument for DRM here is change the technology to overcome a
> political problem?
It's not "my" argument. I'm just saying that RTL plan to use DRM for
that reason.
>>>>The new frequencies on LW and MW they have requested at the ITU are
>>>>279 Khz (Junglinster towards Germany), 567 Khz (Clervoux towards the
>>>>Netherlands), 783 Khz (Beidweiler towards France) and 1098 Khz
>>>>(Clervoux towards Belgium).
>>>I'm happy this is not in my part of the world.
>>Why not. The more channels, the better.
> Just the opposite. One low bit rate crappie sounding DRM signal wastes
> three channels. A good sounding DRM signal would waste twice as many.
Euh. These stations run in the same 9 Khz bandplan as all other
MW-broadcasts. (this is DRM, not IBOC-AM, remember?)
>>Anycase, the biggest user of DRM will probably be not in Europe, but
>>will be in China. (for a very different reason, but that's a different
>>discussion).
> Actually besides sounding like crap DRM biggest problem is that
> broadcasters can start controlling who can listen. DRM would also be
> easier to jam. Small wonder China would go for it.
Well, to be honest, I don't like this neither but I do think it will be
one of the elements that drive DRM worldwide; "political correct" or not.
Like sets which can only tune to certain frequencies, DRM -like any
other digital technology- does allow for receiver which can only tune to
certain stations (like the Chinese state broadcasters), and block tuning
to other transmissions.
But the net result will that there is a market for over half a billion
people for new radios (if we would say that this kind of services is
limited to that half of the Chinese population who lives in urban
areas); and -therefor- allow for the chinese chipset manufacters to
swamp the rest of the world with very cheap receivers.
I do think this can have a very big impact with the advance of DRM into
certain areas (like Africa) which could be very possitive for the use of
radio as a educational tool.
>>>>For SW, they have asked the HFCC for coordination for two
>>>>frequencies: 5990 and 6095 Khz.
>>>I would prefer that the DRM transmissions stay out of the international
>>>broadcast bands and stick to the digital utility frequencies.
>>Why is that. If they are general-public broadcasts, that's where they
>>belong, isn't it?
> No they are a digital mode that interferes with the analog signals I
> want to listen too. ...
Who says that you will not be interested in the stations being
broadcasted in DRM?
Perhaps, as DRM is cheaper to broadcast then AM, you will find more
"interesting" stations on DRM then on AM. (instead of the well-known
rich broadcasters now on shortwave).
> ... They should stick to the part of the spectrum for
> digital mode signals.
AFAIK, the spectrum-allocation is based on principles of "compatibility".
Putting a x-hunderd KW broadcasting-station (analog or digtal) in the
band with utility-stations will produce much more interference than when
it is put in a broadcastind-band "competing" with other high-power
broadcasting-stations.
>>What does a x. KW high-power general-public broadcasting-station do in
>>the same band as medium-power utility-broadcasts?
> Why should a digital mode signal be sitting in the middle of a analog AM
> broadcast band?
Because it is a broadcasting-application.
The other bands (ham, aeronautical, maritime, defence, gouverement, ...)
all have a mix of digital and analog broadcasts and that does not seams
to be a problem overthere.
Sofar, the broadcasting-band has sofar been the only piece where there
hasn't been any digital transmissions, but it looks like that time will
end soon.
>>If these broadcasts are analog or digital are IMHO of no importance.
> I don't know why you would say this. Usage and mode of transmission
> determine what frequency you transmit on. Why should DRM be an exception?
Correct!
And that's why all broadcasting-applications (which need high power as
they are directed to low-gain receivers) must be grouped together in one
band: the broadcasting-bands.
Cheerio! Kr. Bonne.
sdan...@nyc.rr.com
by the dream of making SW reception and audio sound just like FM.
However, it's not quite as good as FM on either count and it's a
bandwidth hog....oh, and there's that pesky problem of drop outs, which
is ultimately far more objectionable than fading. So, DRM is this
exciting new addition to the scene--that's not really quite as good as
either regular shortwave or FM in any of the respects that count.
I think the question is whether DRM even deserves a proper burial.
Kristoff Bonne
sdan...@nyc.rr.com schreef:
> Well, my impression is that DRM is essentally stillborn. ...
A funny thing to say about something that hasn't even started yet and
you already declare it death.
> ... It's inspired
> by the dream of making SW reception and audio sound just like FM.
> However, it's not quite as good as FM on either count and it's a
> bandwidth hog....
Euh. This is DRM, not IBOC-AM. Remember!
Default DRM use the same bandwidth then standard AM, remember?
> ... oh, and there's that pesky problem of drop outs, which
> is ultimately far more objectionable than fading.
See other messages.
> I think the question is whether DRM even deserves a proper burial.
Concidering the fact that DRM will be used for MW/LW, local broadcasts
in the 11 meter, long-distance broadcasting on SW and possible also in
band I or band II; you'll have a difficult job buring it. :-)
Cheerio! Kr. bonne.
Kristoff Bonne
Tom Holden schreef:
>>>c. Analog has sync detection, which eliminates most of the fading most of
>>>the time. This is much better than drop outs.
>>AFAIK, sync detection is against partial-cochannel interference, not
>>against fading.
> Perhaps its greatest benefit is improved immunity from distortion due to
> selective fading, especially that which sucks out the carrier. Suppressing
> one sideband also reduces fading distortion. The Dream software DRM decoder
> also incorporates a synchronous AM, selectable sideband detector. The
> improvement in listenability for a DSB AM signal in the presence of
> selective fading is truly remarkable when it is used in synchronous ECSS
> mode.
Just interested. Does anybody know if the AM-decoding in a "normal
price" SW-receiver is done in hardware or in software (ASIC/DSP)?
> Broadcasters would free spectrum, reduce interference, be more energy
> efficient, maintain compatability with the huge installed base of AM radios
> by converting to SSBc mode.
???
I might have missed something but AFAIK you cannot decode SSBc with a
standard AM-radio, can you?
> ... Radios manufactured with DSP capable of
> synchronous AM selectable sideband would probably require less silicon than
> DRM (read cheaper), be more energy efficient (read eat batteries more
> slowly), be compatable with the huge installed base of DSBAM transmitters
> and the then-growing number of SSBc transmitters. Why don't we hear more
> about this alternative from broadcasters and manufacturers? Have I missed
> something?
DRM has two advantages of this:
- it's a digital system. This means it includes features like auxilairy
content, "Alternative frequency" information, station identification,
multiple streams (e.g. two audio-streams in one DRM transport-stream),
variable bandwidth from 4.5 to 20 Khz, variable modulation-sceme and
error-correction mechanism based on channel quality, easier support for
time- and frequency diversity, single-frequency networking.
It's easier to integrate into combined DAB/DRM chipsets which allows for
an one "integrated" chipset for both systems. It also allows
cross-platform services; e.g. does the "AF"-service work between DAB,
DRM and FM/RDS.
- it's one technology for LW/MW, for SW, for 11 meter "local"
broadcasting and, with the extension of DRM+, for band I and band II.
This creates an enormous market for this, and -therefor- cheaper chipsets.
- And it allows you to lower the transmission-power (and hence the
electrivity-bill).
>>>b. An analog radio with sync detection would sound better than a DRM
>>>radio using the same radio spectrum bandwidth.
>>Do you actually have a DRM-radio? Can you compair?
> While DRM might give the subjective impression of wider frequency response
> and higher signal-to-noise ratio, to fit within a 10 or 20 kHz bandwidth, it
> necessarily uses a very low bitrate lossy codec. I find that listening to
> such codecs is aggravating, moreso than (and very different from) the
> dynamic changes in spectral balance from an AM transmission in moderate
> fades.
>
> Moreover, the DRM spectrum is rectangular - even energy distribution. If we
> take our 10 kHz channel and use SSBc to fill it (carrier at channel edge),
> we will get nearly 10 kHz audio bandwidth. If we also use pre-emphasis (as
> is done in FM), or one of the (ancient) Dolby or dBx type noise reduction
> systems to lift the treble energy in the sideband, we will get a much
> improved S/N. Still very listenable on a conventional DSBAM radio with
> typical IF and AF passbands.
Interest idea. Just interested to know how 10 Khz SSBc would react to
selective fading. As you said in the beginning, the problem is when the
carrier is gone. Wouldn't you have the same problem as with a
DSBAM-receiver?
BTW. AFAIK (correct me if I am wrong) a DSBAM-decoder will completely
chocke on such a signal, so I kind-of miss the reason why you say this
is compatible with a convensional DSBAM-radio.
> Why don't we hear about this approach? It sounds so easy I think I should
> build a transmitter and experiment with it! There must be a catch...
Well, how would such a system react in a situation of two half
co-channel stations. (i.e. one station at 9.900 - 9.910 Khz, and another
channel at 9.905 - 9.915 Khz).
(What is the exact jargon-word for this? co-channel? semi co-channel?)
> Tom
Cheerio! Kr. Bonne.
Kristoff Bonne
Frank Dresser schreef:
>>Well, one of the things about technology is that sometimes "textbook
>>technology" which has existed for long only in books or in very
>>specialised applications (usually defence) just becomes mainstream. Take
>>COFDM or CDMA.
> In the US, much of the pioneering work was done by commercial interests such
> as RCA and AT&T. There was good money to be made trafficing messages around
> the world!
True. When I was at school, we once visited "Oostende radio" (the
maritime radio-station here in Belgium). I was surprised at some of the
things these people manufactered completely by themself.
Does where the times when "operators" still designed and manufactored
things themself. A telco nowdays is just a "user", that's all.
>>Now, I don't think there is anything in the specs for a situation where
>>you would put the same signal twice inside the same DRM transport-stream
>>(one delayed to the other) and give them both the same streamid, so I
>>don't know how a receiver would react to that. (some of them will
>>probably crash :-) )
>>Perhaps that's something to add in the specs.
> But wouldn't a new radio crashing DRM spec make at least some of the new DRM
> radios at least partially obselete? If so, that's bad marketing. Once the
> radios start selling, they're pretty much stuck with whatever works with all
> the DRM radios.
It depends on how you "fit" it into the specs.
Transmitting a time-shifted signal at two different frequencies will
work as it doesn't break the specs. As does twice the same signal inside
one DRM transport-stream (as long as they do not have the same stream-id).
If you then add the "stream 101 is a time-shifted version of stream 102"
information in the SI (System Information) part, a new receiver can use
this information to do time- and frequency-diversity reception.
An "old" receiver will not know how to interprete this information in
the SI-header and just ignore it. He will just see it as two different
streams.
>>True. My personal opinion is that -concidering the interest of quite a
>>lot of the big broadcasters- it will succeed, but we will see.
> The real decision will be made by the public. In the US, the broadcasters
> had a great amount of enthusisiam for AM stereo. There were some radios
> offered, but, for the most part, the public didn't care. AM stereo just
> never caught on, for whatever reason.
> I suppose it's possible that DRM may also be an incomplete success. For
> example, the public might find the occasional SW dropouts too annoying, but
> they might very much like the improved signal to noise ratio on LW.
Well, that's the remark I wanted to make.
The advantage of DRM is that is specification which works in a different
number of enviroments with a number of very different "markets" and
"applications".
This creates a very large market for DRM-chipsets and -even it is not a
success in the beginning in one market- a possible success in other
applications will drive the demand for chips which will drive down the
price.
BTW. Something I forgot to mention the last time.
A couple of months ago, there was a rapport on RNZI about how they think
of using DRM in the pacific ocean region.
Overthere, there are a number of nations which just concist of a large
number of islands with somewhere between some hunderd to some thousand
people on every one of them. Some states concist of almost 100 islands.
As these islands are to far appart to be served by one single
transmittor, they use local FM and AM-relay on individual islands to do
broadcasting.
DRM would have two advantages for them:
- Using DRM in the 18 Khz MW-mode, would allow them to broadcast a
"FM-quality grade" signal from the main island to the other islands,
without the need of use of satellites.
As DRM is digital, you can also "daisychain" transmittors and retransmit
the "feeder" signal (i.e. the DRM-signal) from one island to another
without loss of quality.
DRM over MW would then be the "backbone" transport-layer to get your
signal from the main island to the outmost islands.
However, the rebroadcasting of your program to the general public will
be in analog FM or AM, so that people can continue to use their old
radio-set for the next 10 years or so.
- DRM uses half the broadcasting-power of AM, which is a major advantage
for these islands as most of them are dependend on generators (running
on oil which has to be imported and transported all the way up the most
remote islands) to power their transmittors!
That's one of the advantages of international broadcasting (althou I
downloaded this via the internet). It's always interesting to find out
how people live on the other side of the world and see that things we
find "normal" are not that "normal" overthere. :-)
sdan...@nyc.rr.com
Kristoff Bonne wrote:
> Gegroet,
>
> sdan...@nyc.rr.com schreef:
> > Well, my impression is that DRM is essentally stillborn. ...
>
> A funny thing to say about something that hasn't even started yet and
> you already declare it death.
Well, some ideas are just that bad.
>
>> > I think the question is whether DRM even deserves a proper burial.
> Concidering the fact that DRM will be used for MW/LW, local broadcasts
> in the 11 meter, long-distance broadcasting on SW and possible also in
> band I or band II; you'll have a difficult job buring it. :-)
>
DRM would leap headlong into the hole. Five years from now we won't
even remember what it was.
Kristoff Bonne
sdan...@nyc.rr.com schreef:
>>>>I think the question is whether DRM even deserves a proper burial.
>>Concidering the fact that DRM will be used for MW/LW, local broadcasts
>>in the 11 meter, long-distance broadcasting on SW and possible also in
>>band I or band II; you'll have a difficult job buring it. :-)
> DRM would leap headlong into the hole. Five years from now we won't
> even remember what it was.
We will see. I have learned not to make to much predictions about a new
technology.
Public discussions on the internet have a very long history!!! and
-hence- this is probably the best way to make a complete fool of
yourself if it turns out differently then what you expect.
:-)
Cheerio! Kr. Bonne.
sdan...@nyc.rr.com
consequence. However, I'm not worried about it in this case.
Tom Holden
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
> Gegroet,
>
> Just interested. Does anybody know if the AM-decoding in a "normal price"
> SW-receiver is done in hardware or in software (ASIC/DSP)?
I'm not aware of any radios at any price that do AM decoding by DSP. I
suspect they exist in some form - after all, that is what one would expect
from Software Defined Radio technology. What about these new DRM radios - do
they also do AM and FM demodulation via DSP?
> I might have missed something but AFAIK you cannot decode SSBc with a
> standard AM-radio, can you?
Yes. I might have the acronym wrong - I mean SSB with reduced carrier, not
suppressed. The Canadian time signal transmissions from CHU on 3330 and 7335
kHz use this mode - easily received on the cheapest SW radios.
> DRM has two advantages of this:
> - it's a digital system. This means it includes features like auxilairy
> content, "Alternative frequency" information, station identification,
> multiple streams (e.g. two audio-streams in one DRM transport-stream),
> variable bandwidth from 4.5 to 20 Khz, variable modulation-sceme and
> error-correction mechanism based on channel quality, easier support for
> time- and frequency diversity, single-frequency networking.
I'm aware of this but it's incompatible with the huge installed base......
I'm not sure about your "easier support for" statement - it's true for time
diversity but I can't quite imagine how and why one would need this for an
analog transmission mode so it seems a specious point. Frequency diversity
and SFN is done with AM. One's sense of hearing does a wonderful job of
"error correction" as part of an analog system - the digital system can't
work without its own. Seems like many of the purported advantages are born
out of necessity.
Auxiliary content, AF, station ID's, multiple streams and various bandwidths
and bitrates in DAB surely did not excite the public in this country. Now,
satellite radio with terrestrial fill-ins may be a different matter, and
cable and satellite DTH audio services with images and text certainly are.
The takeup has been pretty good.
> It's easier to integrate into combined DAB/DRM chipsets which allows for
> an one "integrated" chipset for both systems. It also allows
> cross-platform services; e.g. does the "AF"-service work between DAB, DRM
> and FM/RDS.
This may be of interest in those markets that Eureka 147 DAB was adopted
with fair market success (where is that other than the UK?) and maybe where
FM/RDS is likewise deployed but both require that the broadcaster has
multiple transmitters carrying the same program in multiple modes for the
listener to realize the benefit of cross-platform AF service. This may be
more theoretical than practical. The time delay for lockup to DRM or DAB is
so large that AF service using either of them would require dual receivers
so that the alternate frequency is already tuned and locked before the
current
frequency goes unlocked, rather than blindly chasing the AF list.
>
>
> - it's one technology for LW/MW, for SW, for 11 meter "local" broadcasting
> and, with the extension of DRM+, for band I and band II.
So could SSBc and maybe NBFM
>
> This creates an enormous market for this, and -therefor- cheaper chipsets.
Likewise for any mode common to all bands/markets...
>
> - And it allows you to lower the transmission-power (and hence the
> electrivity-bill).
My observations of DRM on shortwave has been that high transmitter power is
still needed - maybe less than for DSBAM. SSBc also saves power.
> Interest idea. Just interested to know how 10 Khz SSBc would react to
> selective fading. As you said in the beginning, the problem is when the
> carrier is gone. Wouldn't you have the same problem as with a
> DSBAM-receiver?
When selective fade knocks out the carrier, you lose lock but not the
modulation, with a "true" synchronous AM detector. There will be an error
distortion, as in asynchronous ECSS, which could be very small for some
considerable time. DRM is not immune to selective fading - the cause is
multipath which causes jitter or spreading of the digital stream and when it
is big enough - no decoding and then wait for re-lock after the jitter has
fallen below the acceptable threshold.
> BTW. AFAIK (correct me if I am wrong) a DSBAM-decoder will completely
> chocke on such a signal, so I kind-of miss the reason why you say this is
> compatible with a convensional DSBAM-radio.
An envelope detector will demodulate as long as there is carrier. There is
increasing distortion as the carrier is reduced relative to sideband below
some level. There would have to be a tradeoff between power savings and
receiver distortion.
> Well, how would such a system react in a situation of two half co-channel
> stations. (i.e. one station at 9.900 - 9.910 Khz, and another channel at
> 9.905 - 9.915 Khz).
>
> (What is the exact jargon-word for this? co-channel? semi co-channel?)
With DSP IF brickwall filtering as in the Dream and SDRadio softwares, I
think it should work very well indeed by setting the filter to less than
5kHz - for the lower of the pair if we assume USB mode for both. The higher
would experience crosstalk from the first for program content whose audio
spectrum extends well above 5 kHz. Conventional AM radios could also be
tuned to minimise interference from the adjacent channel.
How does DRM react to overlapping spectrum from an adjacent or co-DRM? Not
likely very well given its poor performance in the presence of DSBAM or SSB
overlapping its spectrum. DRM SFN's may be another matter but jitter due to
path differences will cause problems somewhere - maybe synchronous SSBc
transmitters could form equally effective SFN's that work with the huge
installed base....
Cheers, Kristoffe. You lead a good discussion.
Tom
Telamon
Kristoff Bonne <compaq...@kristoff.bonne> wrote:
> Gegroet,
>
> Telamon schreef:
> >>Oeps. I am a bit behind scedule replying to this one.
> > No problem.
>
> OK. I'll take your message first this time.
< Snip >
You are not taking my message the first or last time. You just want to
argue non points.
Here is the message, DRM has no real advantage over analog as
implemented.
Saying that "if" this or that was changed then it would be better makes
no difference because it does not exist.
Saying that DRM can have all its benefits and advantages but that you
must compare it to an analog radio without features like sync detection
is just stacking the deck in favor of your non argument.
On air broadcast of time and frequency information on a really low bit
rate channel in poor conditions will not work at all so when you need it
the most it won't work.
If you don't want to, and it's clear that you don't, want to discuss
this factually then that's your problem to deal with.
> Wait, are you telling me that a good DRM-signal in 10 Khz sounds (e.g.
> in stereo) sounds worse then the same signal in AM?
Yeah, I'm telling you that DRM in 10 KHz the sound quality sucks.
> Do you have audio-samples to support this claim?
Yes, on the DRM web site. They have example of strong and weak signal
DRM reception and compare it to analog. I've written this for the third
and last time. Here is another thing I'm writing for the last time and
that's low bit rate audio sound sucks whether the source is a DRM
broadcast, streamed from the Internet or a recording.
Digital signals don't belong in the analog AM broadcast band where they
occupy at least three channels. I don't want them there and most people
don't want those transmission there either.
Your desire to be a sucker for DRM is a personal problem as I see it.
--
Telamon
Ventura, California
craigm
>>Wait, are you telling me that a good DRM-signal in 10 Khz sounds (e.g.
>>in stereo) sounds worse then the same signal in AM?
>
>
> Yeah, I'm telling you that DRM in 10 KHz the sound quality sucks.
>
>
>>Do you have audio-samples to support this claim?
>
>
> Yes, on the DRM web site. They have example of strong and weak signal
> DRM reception and compare it to analog. I've written this for the third
> and last time. Here is another thing I'm writing for the last time and
> that's low bit rate audio sound sucks whether the source is a DRM
> broadcast, streamed from the Internet or a recording.
>
I listened to the samples on the sites and all of the "High Quality" DRM
samples sounded better to my ears than the corresponding analog signal.
The "Robust Quality" sample had a lot of digitizing artifacts, but that
used a very low bit rate. However, it may be preferable to the analog
equivalent. That would be a personal judgement, some will prefer the
analog, some the digital.
From what I hear in the samples, any of the 64 QAM/"High Quality"
signals is better than the analog equivalent. To me, DRM has good potential.
craigm
Telamon
craigm <no...@domain.invalid> wrote:
This may boil down to personal taste. I don't like the sound of the
"high quality" mode either although is certainly much better than the
lower bit rate. Even in high quality mode I still hear annoying audio
artifacts that I would not chose to listen too.
DRM is a lame implementation. For the cost of changing over to this
system I would want a bigger payoff in performance and functionality
than it currently provides.
There is also to great a risk in this system being abused to limit
information that is now world wide. I would not want that to change in
any way.
--
Telamon
Ventura, California
RHF
.
Here is a possible "Market Indicator" about the Future and Fate
of both DRM on Shortwave and IBOC on AM and FM Broadcast Radio.
.
The proposed Mini-CCRadio that is scheduled for release this fall.
So do you see DRM or IBOC listed as a feature or an option ? - NO !
http://www.ccrane.com/radios/am-fm-radios/mini-cc-radio.aspx
.
The next big indicator will be the new Eton/Grundig/Tecsun, Sangean
and Degen Radios that will be released in the next few years.
Will DRM and IBOC be a feature or an option with these Radios :
Or simply something that is not there; and thereby going nowhere [.]
.
Will the replacement for the Grundig Satetellit 800 Millennium Radio
feature DRM on Shortwave and IBOC on AM and FM Broadcast Radio ?
If not... then the Manufactures are saying a Big "NO" to both DRM
for Shortwave and IBOC for AM and FM Broadcast Radio.
http://groups.yahoo.com/group/Eton-Elite-E2-DRM-IBOC-Radio/
Will it be named the Eton {Elite} E2 with "DRM & IBOC" Radio ?
.
IBOC may be saved by the Automobile Manufactures if they as a Group
start placing IBOC capable AM and FM Broadcast Radios in their new
Cars and Trucks. BUT ! - These same Auto Makers are behind both XM
and Sirius Satellite Radio Systems and Service : Which has a bigger
pay-off and pay-back for them then IBOC could have.
.
Again "The Market Makers" will decide the Future and Fate of
both DRM on Shortwave and IBOC on AM and FM Broadcast Radio.
.
.
something to think about ~ RHF
.
.
. .
Telamon
"RHF" <rhf-new...@pacbell.net> wrote:
Here is one I know about. Both links are actually for the same radio by
two of the companies that are working together on it.
<http://www.codingtechnologies.com/products/applic_broadcast.htm>
<http://www.mayah.com/newsletter/newsletter6-05.htm>
Coding technologies owns some of the code and algorithms that operate in
the radio. Licensing the code is their way to make money on this venture.
Mayah is an electronics manufacturer.
This thing looks like a portable but it's not because it does not
operate on batteries. It uses a 100-240VAC, 1 Amp power supply so you
would not get very far on AA, C or D batteries.
I wrote years ago that DRM portables would have a power problem. You
have to run a lot of processing to get the audio. In order to get the
power down to reasonable levels will require CMOS custom IC's that take
big bucks to develop. That is not going to happen unless the entire
coding and all algorithms become public property.
--
Telamon
Ventura, California
John Newman
wrote:
>Again "The Market Makers" will decide the Future and Fate of
>both DRM on Shortwave and IBOC on AM and FM Broadcast Radio.
Definitely. Don't forget also about the new market makers like the
WinRadio. DRM is equisitely suited for software-defined radios:
http://www.winradio.com/drm
John
D Peter Maus
I work with a couple of high end receiver manufacturers that are
right now dealing with the question of IBOC. The licensing costs extend
not only to receiver manufacturers, but to the broadcasters as well, and
right the costs of implementing IBOC are steep. Mid 5 figures in most
cases. And that's becoming a roadblock for the implementation of IBOC on
the transmission end for many broadcasters. DRM is little diffferent in
that regard. What movtivate broadcasters to move this way is two fold.
One is that Powell's FCC mandated that all new broadcast technologies
must be digital. Period. TV, Radio. Digital. The other has been the holy
grail of broadcasters since David Sarnoff bludgeoned his first
competitor: Subscription over-the-air broadcast. Make no mistake, that's
coming.
The technical advantages of Ibiquity on FM are minimal. In A-B tests
of FM IBOC, listeners have noted a difference, but not a clear
preference for HD on FM, but only when the analog signal was processed
in the traditional manner. And as many preferred analog as HD. When both
were unprocessed, listeners couldn't tell analog FM from IBOC HD Radio.
So, the value, at least for now, is in the buzzword.
There have been some minor, improvements in signal areas where
multipath is an issue. Instead of picket fencing, in severe areas,
there are drop outs, when the error correction fails. Dropouts, in the
tests I've been involved in, have been rare. Multipath resistance in
most cases is actually quite good.
On the AM side, HD radio is an enormous noise source. With at least
two broadcasters in Chicago turning off their HD signal to protect their
Milwaukee stations from the QRM. Audio performance, again, is of
questionable benefit, because of the digital artifacts and low bit
encoding. Some I've heard have been downright awful.
In AM modulated signals, DRM, in tests I've been involved in, has
been a clear improvement over Ibiquity in regard to audio quality. Where
bandwidth exists, the audio can be quite striking. But that depends on
the bitrate, and often, the stability of the signal. QRM, however, is an
enormous problem for DRM, like Ibiquity, and both have proven to take
more bandwidth than originally promised. Creating problems for the
analog listener. Many car radios extant, are unable to separate the
digital hash from the analog audio on the AM side. And especially the AM
hash from first, second, and often third adjacent stations, in and out
of market. Receivers are complex, and expensive, and they consume huge
amounts of power, rendering battery operation problematic for the casual
user. For hobbyist geeks like the members of this group, that's less of
a problem. But, as has been pointed out in so many tasteless ways,
dramatically and bluntly so in the case of Mark Byford, we're of no
consequence in the grand scheme of things broadcast.
Radio Nederland has stated time and again that they're committed to
Shortwave, and have embraced DRM. They're by far in the minority of SW
broadcasters in their commitment, and with political and economic forces
rising to curb production of, and make illegal receivers capable of non
domestic broadcast reception (Billy Tauzin has been pushing a bandplan
for US type accepted receivers that would not permit the public access
to non broadcast media for years, now) and BPL threatening much of non
broadcast spectra, the outlook for market and DRM driven expansion of SW
in the US is dim. With most national networks moving to FM in Europe,
and Worldspace elsewhere, the overall outlook for SW is not looking too
good. And politically, digital modulation, means local-only reception,
whether UKW or MW, and that means the ability to control the public's
access to information. Don't think for a minute that's not on the radar
for most governments.
Broadcasters endorse any moves that curtail domestic non broadcast
listening, because it puts them in a powerful and exclusive position in
control of vital information, without fear of contradiction from
alternate sources. It also puts subcription over-the-air broadcast
within grasp. And FCC has stated it's desires to move all broadcast away
from analog modulation schemes. But, as has been pointed out before,
licensing of the technology is expensive. So broadcasters' motivations
are mixed.
All of which means a more or less chaotic state of affairs for both
DRM and Ibiquity, both in the US and abroad. And if the market is to
decide the fate of these technologies, then we should take a lesson from
another market driven broadcast innovation: AM stereo.
Market drive in broadcast is a hit or miss affair. FM had been
languishing on the edges of extinction since Amstrong took his beating
from Sarnoff. It wasn't until FCC mandated in the 60's that all new
radios produced were to have both AM and FM stages, that FM listening
began to take off. Even though FM radios had been available and
affordable for years. Similarly, UHF TV had existed for decades, with
survivability hovering near zero for UHF broadcasters until FCC mandated
that all new TV sets would carry all UHF channels. Color TV took more
than two decades to catch fire. FM stereo didn't become universal until
the late 70's. AM stereo...well, it was a good idea at the time. And we
should all thank Leonard Kahn for his experiments in AM stereo 50 years
ago. It could have been fun. We can certainly point to the market drive
for THAT success.
So, without an immediate public embrace of the technology, it's not
likely that DRM or Ibiquity will take off. And the public isn't likely
to be spending $500 or more on a radio for debatable improvements in
performance, when 'just as good' technology is available for less than
$10 at any Wal-Mart. And if you think that high performance audio is an
issue with the public, then consider that people are getting their music
on their cell phones, for Heaven's sake. $500 radios for IBOC or DRM, in
that climate is, to borrow from Reverend Johnson in 'Blazing Saddles,'
"...just jerking off."
Now, a Federal mandate for digital modulation schemes is in place.
And a Federal type acceptance and conversion timetable isn't too far off.
But then, we were supposed to have all been switched over to HD TV by
the first of 2006, too. And Michael Powell is gone. And there is no
mandate for receiver manufacturers to include digital demodulation in
all new products.
Don't expect big things for DRM, or Ibiquity, anytime soon.
Kristoff Bonne
Telamon schreef:
>>Here is a possible "Market Indicator" about the Future and Fate
>>of both DRM on Shortwave and IBOC on AM and FM Broadcast Radio.
>>The proposed Mini-CCRadio that is scheduled for release this fall.
>>So do you see DRM or IBOC listed as a feature or an option ? - NO !
>>http://www.ccrane.com/radios/am-fm-radios/mini-cc-radio.aspx
(...)
> Here is one I know about. Both links are actually for the same radio by
> two of the companies that are working together on it.
> <http://www.codingtechnologies.com/products/applic_broadcast.htm>
> <http://www.mayah.com/newsletter/newsletter6-05.htm>
(...)
> I wrote years ago that DRM portables would have a power problem. You
> have to run a lot of processing to get the audio. In order to get the
> power down to reasonable levels will require CMOS custom IC's that take
> big bucks to develop. That is not going to happen unless the entire
> coding and all algorithms become public property.
One year is in etternaty in electronics. :-)
Here are some press releases concerning DRM/DAB of the IFA
(Internationale Funk Aufstellung) Berlin and IBC Amsterdam (both where
held earlier this month):
One in english:
http://www.infosat.lu/Meldungen/?srID=53&msgID=17027
Another one:
http://www.4rfv.co.uk/industrynews.asp?ID=43833
One in dutch buth with some pictures:
http://home.planet.nl/~rickvdw/digitaal/DRM-IBC2005/
If you run "drm dab receivers ifa ibc" throu your favourite
search-engine, you'll come up with more then sufficiant links.
These things are geared up for the European market: FM/RDS, AM (no SSB),
DAB, mp3 and wma-playback, SD/MMC interface, ...
Also note that the sangean radio builds on the design of their DAB-range
not on their range of SW-receivers.
So I guess these models will only have either MW and LW, and a limited
number of SW-bands (probably only the "local" bands), but it looks
logical they will work on this design in other variations, like
FM/AM/IBOC-FM/IBOC-AM for the US, or AM/FM/SSB/DRM for shortwave-receivers.
The receivers are expected by the end of the year, so we will know more
about features and prices.
Also note that the power-consumtion issue (as on the mayah) has been
solved as they have been working on DAB/DMB modules for inside
mobile-phones (DAB/DMB uses more power then DRM).
More information about the chipset can be found here:
http://focus.ti.com/docs/apps/catalog/tisolutions/tisolutions.jhtml?templateId=938&path=templatedata/cm/general/data/audio_digrad_drm
Finally notice that these radio's are market under the "DR" logo, which
combines DAB and DRM. So, this is not a "DRM" radio, but a "DR" radio!
Cheerio! Kr. Bonne.
cuh...@webtv.net
politicians want us all to pay through the teeth for radio and tv.I am
already paying over $40.00 each month for my DirecTV subscription,over
140 tv channels and only a hand full of them are worth watching,in my
opinion.Will Analog Radio become obsolete someday? By the way,the Stupid
fcc needs to get that Stupid powell guy on out of there.Or did they
already?
cuhulin
cuh...@webtv.net
powell refused to send some Helicopters to Somalia even though our
U.S.Troops over there had asked for them.The rest is History.
www.realchange.org (Skeleton Closet) I would never even buy a
hamburger if any of them powells were flipping them.
cuhulin
David
You get what you pay for.
Powell is gone.
clifto
> Market drive in broadcast is a hit or miss affair. FM had been
> languishing on the edges of extinction since Amstrong took his beating
> from Sarnoff. It wasn't until FCC mandated in the 60's that all new
> radios produced were to have both AM and FM stages, that FM listening
> began to take off.
I never heard of this. Further, from the sixties on, AM-only radios have
been available all over the USA. What made FM take off was underground
radio.
--
If John McCain gets the 2008 Republican Presidential nomination,
my vote for President will be a write-in for Jiang Zemin.
D Peter Maus
> D Peter Maus wrote:
>
>> Market drive in broadcast is a hit or miss affair. FM had been
>>languishing on the edges of extinction since Amstrong took his beating
>>from Sarnoff. It wasn't until FCC mandated in the 60's that all new
>>radios produced were to have both AM and FM stages, that FM listening
>>began to take off.
>
>
> I never heard of this. Further, from the sixties on, AM-only radios have
> been available all over the USA.
Actually, for a while, they weren't.
What made FM take off was underground
> radio.
>
What made FM take off was the popularity of mass appeal programming
found by listeners migrating to FM as FM radios became more widely
available. FM had been around for more than 20 years by the time the
general market discovered it, with programming limited to classical
music, because ASCAP royalties did not have to be paid, and beautiful
music formats because of it's cost effectiveness. Most FM stations had
short lifespans until the 60's, because there was just no one in any
numbers listening. Primarily because of the limited value of making the
investment in an FM capable radio for what little was actually on the
bands. Even as late as the 60's, FM capable radios were expensive.
Portables often running $50 or more. My first FM was a Raleigh 9
transistor, in the late 60's, after FM radios became manufactured in
numbers, and it still cost almost $30, a lot of money then, when AM
radios had been available for half that.
Underground radio went dark for the same reasons most FMs went dark
in the late 40's and 50's: there weren't enough listeners to support it.
At the same time, Top 40 and AOR radio were stealing listeners from AM
in droves, dwarfing the size of underground audiences.
D Peter Maus
Let me make a clarification to that. I'm not suggesting that AOR and
Top 40 were around in the late 40's and 50's. But they, were, in fact,
latecomers to the FM band around the time that underground radio was in
it's final days. Stations like KDNA, ST Louis lost their asses to KSHE
(AOR), KADI (AOR) and KSLQ (Top 40.)
KDNA never pulled appreciable numbers out of a few high school and
college kids, and was replaced with Schulke Beautiful Music as KEZK. In
fact, KDNA's audience was dwarfed by KXOK (AM Top 40), and even among
the high school FM afficionados of the time, didn't make a strong
showing against KSLQ. College kids were listening more to KSHE than KDNA.
What KDNA did do well, was introduce non mainstream music to an
audience that was already hungering for something that was out of the
popular tide. John McLaughlin, Robbie Basho, Ravi Shankar, and Leo
Kottke were staples of KDNA programming. I heard my first Firesign
Theatre on KDNA. But the numbers tuning in, like most alternative
formats, were very small.
KACO, also licensed in St Louis attempted undeground radio, but the
guy who owned it couldn't affort the upkeep, eventually running only 12
hours a day, and spinning the tunes himself. Ask anyone how many times a
day he played the theme from "Mannix." By the time KACO went away, me
and the guy who owned it were the only ones who knew it was there.
Some underground stations made a bit of noise. Some actually did
reasonably well. But they are dark today for the same reasons as any of
the stations who ever went dark: Lack of interest.
Shame, really. Some of them, even KDNA, were actually quite good and
well executed.
Underground radio was an interesting historical moment in
broadcasting's colourful history, but it was hardly the impetus claimed
for it.
>
Kristoff Bonne
cuh...@webtv.net schreef:
> Everything digital,,, subscription radio. ...
Please do not equate "digital" with "subscription". Overhere in Europe,
all digital radio-stations are FTA and for TV, there are more
TV-stations available in the clear in DVB then in PAL.
E.g., PAL has been stopped for terrestial broadcasts in some areas in
Germany (like in Berlin) and has meant that the number of stations
available (in the clear) in DVB-T has been multiplied by 3 to 4
compaired to what was available in OTA PAL.
Most of these stations where already available (FTA) over digital
satellite, so these are not "junk" stations.
Concerning radio, the fact that subscription-radio can exists in the US
says more about the low quality of "normal" radio then the fact that
these satellite-radios are digital.
With the exception of one packet on Ku-band which is sold as a "add on"
to subscription-TV, all digital radio-broadcasts in Europe are FTA!
> cuhulin
Cheerio! Kr. Bonne.
cuh...@webtv.net
St.Louis,Missouri all the time up untill he retired.
cuhulin
cuh...@webtv.net
Telamon
Kristoff Bonne <compaq...@kristoff.bonne> wrote:
The links I provided point to the only SW DRM concept radio that I know
of other than rack mount units.
The rest need a computer to process the audio.
The one SW concept radio I pointed to can not run on batteries.
The statements that I have seen before about DRM being an open standard
are as far as I see false because the software is not in the public
domain.
For this among other reasons the name "Deception Radio Mondiale" sticks.
Now you have heard the rest of the story... for now at least.
--
Telamon
Ventura, California
Kristoff Bonne
Telamon schreef:
>>>>The proposed Mini-CCRadio that is scheduled for release this fall.
>>>>So do you see DRM or IBOC listed as a feature or an option ? - NO !
>>>>http://www.ccrane.com/radios/am-fm-radios/mini-cc-radio.aspx
>>>Here is one I know about. Both links are actually for the same radio by
>>>two of the companies that are working together on it.
>>><http://www.codingtechnologies.com/products/applic_broadcast.htm>
>>><http://www.mayah.com/newsletter/newsletter6-05.htm>
>>Here are some press releases concerning DRM/DAB of the IFA
>>(Internationale Funk Aufstellung) Berlin and IBC Amsterdam (both where
>>held earlier this month):
>>One in english:
>>http://www.infosat.lu/Meldungen/?srID=53&msgID=17027
>>Another one:
>>http://www.4rfv.co.uk/industrynews.asp?ID=43833
>>One in dutch buth with some pictures:
>>http://home.planet.nl/~rickvdw/digitaal/DRM-IBC2005/
> The links I provided point to the only SW DRM concept radio that I know
> of other than rack mount units.
Well, there are a lot more of them. :-)
(see the links I provided).
> The statements that I have seen before about DRM being an open standard
> are as far as I see false because the software is not in the public
> domain.
Like this one?
http://sourceforge.net/projects/drm/
> For this among other reasons the name "Deception Radio Mondiale" sticks.
Looks to me like the Deception is more in your mind then in reality. :-)
Cheerio! Kr. Bonne.
Telamon
Kristoff Bonne <compaq...@kristoff.bonne> wrote:
> Gegroet,
>
>
> Telamon schreef:
> >>>>The proposed Mini-CCRadio that is scheduled for release this fall.
> >>>>So do you see DRM or IBOC listed as a feature or an option ? - NO !
> >>>>http://www.ccrane.com/radios/am-fm-radios/mini-cc-radio.aspx
>
> >>>Here is one I know about. Both links are actually for the same radio by
> >>>two of the companies that are working together on it.
> >>><http://www.codingtechnologies.com/products/applic_broadcast.htm>
> >>><http://www.mayah.com/newsletter/newsletter6-05.htm>
>
> >>Here are some press releases concerning DRM/DAB of the IFA
> >>(Internationale Funk Aufstellung) Berlin and IBC Amsterdam (both where
> >>held earlier this month):
> >>One in english:
> >>http://www.infosat.lu/Meldungen/?srID=53&msgID=17027
> >>Another one:
> >>http://www.4rfv.co.uk/industrynews.asp?ID=43833
> >>One in dutch buth with some pictures:
> >>http://home.planet.nl/~rickvdw/digitaal/DRM-IBC2005/
>
> > The links I provided point to the only SW DRM concept radio that I know
> > of other than rack mount units.
>
> Well, there are a lot more of them. :-)
> (see the links I provided).
No there isn't with the links you provided.
> > The statements that I have seen before about DRM being an open standard
> > are as far as I see false because the software is not in the public
> > domain.
>
> Like this one?
> http://sourceforge.net/projects/drm/
No I don't like it. This is another computer - radio. You do realize
that most of these units need a computer to operate? These are not stand
alone radios. The link I provided is the one stand alone SW radio that I
know about.
The other links are not SW radios or they need computers to operate or
they are rack mount units that are and will continue to be very
expensive. The rack mounts are not consumer units.
> > For this among other reasons the name "Deception Radio Mondiale" sticks.
> Looks to me like the Deception is more in your mind then in reality. :-)
I don't find this humorous.
I keep to the facts and you just play around.
You don't pay attention to well either.
You ask about something I posted three times about and don't seem to
understand the difference between a stand alone radio and one that needs
a computer to process the audio.
--
Telamon
Ventura, California
craigm
>>>The statements that I have seen before about DRM being an open standard
>>>are as far as I see false because the software is not in the public
>>>domain.
>>
>>Like this one?
>>http://sourceforge.net/projects/drm/
>
>
> No I don't like it. This is another computer - radio. You do realize
> that most of these units need a computer to operate? These are not stand
> alone radios. The link I provided is the one stand alone SW radio that I
> know about.
>
The reply was in response to your statement that the software was not in
public domain. Source code is available so your argument fails.
Just because the software runs on a computer today, doesn't mean it must
always run on a computer. Initially MP3 encosded music only ran on a
computer. Now you can easily find battery operated MP3 players.
There are some that run 70 hours on a single AAA battery. Battery life
does not need to be an issue either.
> The other links are not SW radios or they need computers to operate or
> they are rack mount units that are and will continue to be very
> expensive. The rack mounts are not consumer units.
>
>
Once a semiconductor manufacturer produces an ASIC for DRM it will be
possible to produce battery operated radios with DRM. A receiver
manufacturer could also create a custom ASIC.
craigm
Kristoff Bonne
Not much time now. Just a quick reply:
Telamon schreef:
>>>>Here are some press releases concerning DRM/DAB of the IFA
>>>>(Internationale Funk Aufstellung) Berlin and IBC Amsterdam (both where
>>>>held earlier this month):
>>>>One in english:
>>>>http://www.infosat.lu/Meldungen/?srID=53&msgID=17027
>>>>Another one:
>>>>http://www.4rfv.co.uk/industrynews.asp?ID=43833
>>>>One in dutch buth with some pictures:
>>>>http://home.planet.nl/~rickvdw/digitaal/DRM-IBC2005/
>>>The links I provided point to the only SW DRM concept radio that I know
>>>of other than rack mount units.
>>Well, there are a lot more of them. :-)
>>(see the links I provided).
> No there isn't with the links you provided.
Take a look at the pictures in the last link.
Anycase, here's another link from the BBC news website:
http://news.bbc.co.uk/1/hi/technology/4237010.stm
We will see by this year's end when these things are actually in the
shops what the actual specifications of these radios will be.
My guess is that the number of shortwave-bands on these radios will be
limited.
>>>The statements that I have seen before about DRM being an open standard
>>>are as far as I see false because the software is not in the public
>>>domain.
>>Like this one?
>>http://sourceforge.net/projects/drm/
> No I don't like it. This is another computer - radio. ...
Of course it is. This is a reply to your comment that the source-code
for the DRM SDRs is not available. It is and it is GPLed.
The best prove of it is HAMDRM, the version of DRM redesigned to operate
in 3 Khz. Their code is based on the code of DREAM that you can find in
the link I provided.
> The other links are not SW radios or they need computers to operate or
> they are rack mount units that are and will continue to be very
> expensive. The rack mounts are not consumer units.
OK. I think there was some "communication-error" between us. A "rack
mountable" (to me) is a device you place inside a rack, which is usually
professional equipement to be placed inside a computer or telecom-room.
(In this case, I though you talked about the "professional"
DRM-receivers and DRM-monitors made by companies who also build
transmittors).
A "PC-decoder" (i.e. something used by hobbyists and HAMs) I would call
a "SDRs" (Software Defined Radio).
The Mayah was a halfway solution as it used a generic DSP-processor to
do DRM-decoding (which explains why it use that much power). These next
generation DAB/DRM radios are based on ASIC-designs.
>>>For this among other reasons the name "Deception Radio Mondiale" sticks.
>>Looks to me like the Deception is more in your mind then in reality. :-)
> I don't find this humorous.
> I keep to the facts and you just play around.
No I don't.
I like to keep a discussion as "clean" as possible too, but I think
there simply was a miscommunication between us.
But, if you use a name like 'Deception', you'll need to make sure that
you can "prove" your statement. Fact is
- that "standalone" DRM-radios do exist.
- that the source-code of DRM is publically available.
Cheerio! Kr. Bonne.
RHF
.
DRM - The Signal Quality and Distance Factor - - -
Is there a Natural Problem Beyond the Limits of Technology ?
.
DRM may in-fact be a better transmission and reception process of
getting "The Message Through" around Europe or within China and
India. Within a Clearly Improved Quality Performance Range of
2000 Km (1200 Miles)
.
BUT ? Will DRM be a better transmission and reception process to
get 'the message through' at the Greater Distances involved with :
Trans-Atlantic? Trans-Pacific? Trans-Continental?
When current AM Radio Analog Fade and Fading (DRM Drop-Outs)
are a major inhibitor to Quality Shortwave Radio Reception.
When the Quality Signal Range is required to be 4000 Km; 8000 Km;
16000 Km and more.
.
Once Again - Is there a Natural Problem Beyond the Limits of Technology
?
Will the Distance Factor "Impact" The Signal Quality of DRM ?
.
.
better is not always the best ~ RHF
.
.
. .
Kristoff Bonne
> DRM - The Signal Quality and Distance Factor - - -
> Is there a Natural Problem Beyond the Limits of Technology ?
> DRM may in-fact be a better transmission and reception process of
> getting "The Message Through" around Europe or within China and
> India. Within a Clearly Improved Quality Performance Range of
> 2000 Km (1200 Miles)
(...)
> When the Quality Signal Range is required to be 4000 Km; 8000 Km;
> 16000 Km and more.
I have a train to catch in half an hours so just a quick message before
I get out of here:
Well, as the British say "the proof of the pudding is in the eating",
the best way is to try it yourself.
But, for there are some indications about the possibility on the website
of Chris Mackerell in New Zealand. He has some interesting audio-samples
online: http://www.owdjim.gen.nz/chris/radio/DRM/
Including a repport of the number of audio-frames received and the audio
of it. (the only thing that I find a pitty is that these audio-samples
have been compress a second time using a lossy codec, creating a "codec
cascade" effect).
There are examples with a lot of packetloss and some with excellent
reception; some from as far as Europe (20000 km from New-Zealand).
But, the best it to try it out yourself. (but I don't have a DRM radio
neither, so who am I to say what you should do. :-)))
Cheerio! Kr. Bonne.
Telamon
Kristoff Bonne <compaq...@kristoff.bonne> wrote:
I'm not playing any more of your yes it is and no it isn't crap. The
link above points to the same radio the other links you provided already
show that this is NOT A SW RADIO. It's AMBCB and FM like the rest. Now
I've lost count of how many times I have posted - the one I showed you
is the ONLY DEMONSTRATION SW DRM RADIO IN ANY OF THE LINKS.
The few other exceptions are very expensive professional rack mount OR
computer based processing. You have not made one point in regurgitating
the DRM consortiums press releases. I've already read them and I don't
need you to point me to them. It would be OK if the links proved your
assertions but they don't.
The computer software down load gives you TEMPORARY and not PERMANENT
use. The rights are NOT given away with this software. This is just one
of the deceptions about DRM is that the coding is free and anybody can
use it as see fit. If you can't see that then to bad for you.
You are full of crap and I'm not playing your Trolling game.
< Plonk >
--
Telamon
Ventura, California
Telamon
craigm <no...@domain.invalid> wrote:
> Telamon wrote:
>
> >>>The statements that I have seen before about DRM being an open standard
> >>>are as far as I see false because the software is not in the public
> >>>domain.
> >>
> >>Like this one?
> >>http://sourceforge.net/projects/drm/
> >
> >
> > No I don't like it. This is another computer - radio. You do realize
> > that most of these units need a computer to operate? These are not stand
> > alone radios. The link I provided is the one stand alone SW radio that I
> > know about.
> >
>
> The reply was in response to your statement that the software was not in
> public domain. Source code is available so your argument fails.
You do not have the rights to the software, those rights are reserved.
For the time being you can down load and compile it on a local machine
for your own use. If the rights holder tell you to stop using it then
that's it. If money is demanded then you will have to pay it. There are
many ways this can be enforced.
There is one stand alone demonstration radio. I provided the link to it.
The others are multi kilo buck professional rack mount units that
consumers are not going to buy. All the other links by the DRM Troll
point to AMBCB and FM NOT SW RADIOS or computer assisted radios.
So the argument that "DRM consumer penetration into SW" is false.
> Just because the software runs on a computer today, doesn't mean it must
> always run on a computer. Initially MP3 encosded music only ran on a
> computer. Now you can easily find battery operated MP3 players.
So what.
> There are some that run 70 hours on a single AAA battery. Battery life
> does not need to be an issue either.
Again so what.
> > The other links are not SW radios or they need computers to operate or
> > they are rack mount units that are and will continue to be very
> > expensive. The rack mounts are not consumer units.
> >
> >
>
> Once a semiconductor manufacturer produces an ASIC for DRM it will be
> possible to produce battery operated radios with DRM. A receiver
> manufacturer could also create a custom ASIC.
Yeah that's the no brainer requirement it will take to create a radio
that will operate on batteries. Make no mistake about this, battery life
will be shorter than the current generation radios.
So who do you think is going to spend hundreds of thousands of dollars
to make ASIC's to do this?
--
Telamon
Ventura, California
Tom Holden
news:telamon_spamshield-8...@newsclstr02.news.prodigy.com...
[snip]
> I've lost count of how many times I have posted - the one I showed you
> is the ONLY DEMONSTRATION SW DRM RADIO IN ANY OF THE LINKS.
1. http://www.mayah.com/products/products-drm.htm
2.
http://www.himalaya.com.hk/index.php?option=com_content&task=view&id=14&Itemid=28&lang=en
Both above are short-wave. Of course, SW could mean software and that adds a
few more.
I thought the discussion on performance, technology, market, motivators,
politics was most interesting - thanks to Kristoff for initiating it. It
would be nice to continue the discussion, respectfully.
Regards,
Tom
Peter Maus
> Telamon wrote:
>
>>>> The statements that I have seen before about DRM being an open
>>>> standard are as far as I see false because the software is not in
>>>> the public domain.
>>>
>>>
>>> Like this one?
>>> http://sourceforge.net/projects/drm/
>>
>>
>>
>> No I don't like it. This is another computer - radio. You do realize
>> that most of these units need a computer to operate? These are not
>> stand alone radios. The link I provided is the one stand alone SW
>> radio that I know about.
>>
>
> The reply was in response to your statement that the software was not in
> public domain. Source code is available so your argument fails.
>
Availability for development and beta testing is not the same as
public domain. The source code is not available for unrestricted use.
Like iBiquity, use of DRM source code in distributed products,
commercial or otherwise, incurs license fees, which can be costly. On
both transmission and reception ends.
> Just because the software runs on a computer today, doesn't mean it must
> always run on a computer. Initially MP3 encosded music only ran on a
> computer. Now you can easily find battery operated MP3 players.
Good case in point. You are aware that Thomson/Fraunhofer receives a
royalty on every MP3 player sold. MP3 is a licensed technology. And
early on, MP3 was not inexpensive. My first MP3 encoder cost more than
$300. "Professional" versions (feature sets for heavy users in
commercial environments) could cost twise that. Though not so costly
today, they're still not free.
But MP3 had wide application in general market audio file
transmission/reception at a time when such technology solved problems
faced by large numbers of users on street level that were not solvable
by other means at the time.
For DRM, also a licensed technology, like the wire recorder, which
also met street level users' needs, there are already technologies in
place and in use that meet the same user expectations or better for the
same money or less, while presenting greater convenience than current
DRM receivers allow.
Whether or not DRM, or iBiquity, take off remains to be seen, but the
outlook is questionable. The technical advantages against competing
technologies are, at best, minimal. The technical obstacles are many.
And the costs for both broadcasters and listeners are high.
And the public are uninterested.
As with AM Stereo, there is no public clamor for these technologies
to be widely implemented. If the public were to make such noise, there
would be nothing to stop the tidal wave of implementation. Because there
would be money in it. Large money.
Returning to the example of MP3, there was public and professional
demand for smaller audio files due to the high cost of storage and the
limited transmission rates available at the time. MP3 met this handily.
Today, with storage cheap and transmission rates high, MP3 is more of an
institution than a necessity. As evidenced by the number of portable
players that now embrace uncompressed files.
But for now, there is no public clamor for DRM. And absent a
regulatory mandate, without a public demand there is no motivation for
implementation.
The market driven future for DRM, and iBiquity, is dim.
craigm
> In article <cWRZe.21962$X6.1...@fe05.lga>,
> craigm <no...@domain.invalid> wrote:
>
>
>>Telamon wrote:
>>
>>
>>>>>The statements that I have seen before about DRM being an open standard
>>>>>are as far as I see false because the software is not in the public
>>>>>domain.
The software does not have to be in the public domain for the standard
to be open. The standard is one thing, the software is an implementation
of the standard. I can write software that complies with an open
standard and sell it without putting the source in the public domain.
>>>>
>>>>Like this one?
>>>>http://sourceforge.net/projects/drm/
>>>
>>>
>>>No I don't like it. This is another computer - radio. You do realize
>>>that most of these units need a computer to operate? These are not stand
>>>alone radios. The link I provided is the one stand alone SW radio that I
>>>know about.
>>>
>>
>>The reply was in response to your statement that the software was not in
>>public domain. Source code is available so your argument fails.
>
>
> You do not have the rights to the software, those rights are reserved.
> For the time being you can down load and compile it on a local machine
> for your own use. If the rights holder tell you to stop using it then
> that's it.
If you follow the requirements of the GPL, then the rights holder won't
tell you to stop using it.
If money is demanded then you will have to pay it.
Per the GPL, any money is for distribution costs. Since the links were
for a free download site, there is no cost, now or in the furute.
There are
> many ways this can be enforced.
Yes, but you would have to violate the terms of the GPL.
>
> There is one stand alone demonstration radio. I provided the link to it.
> The others are multi kilo buck professional rack mount units that
> consumers are not going to buy. All the other links by the DRM Troll
> point to AMBCB and FM NOT SW RADIOS or computer assisted radios.
>
> So the argument that "DRM consumer penetration into SW" is false.
>
>
>>Just because the software runs on a computer today, doesn't mean it must
>>always run on a computer. Initially MP3 encosded music only ran on a
>>computer. Now you can easily find battery operated MP3 players.
>
>
> So what.
You argue that DRM is primarily limited to computers and that is an
issue for you. I provided an example of a technology that was initially
limited to computers and is now available in low cost devices that fit
in a pocket. The point being, the same can happen with DRM.
>
>
>>There are some that run 70 hours on a single AAA battery. Battery life
>>does not need to be an issue either.
>
>
> Again so what.
You argue that the technology to turn a digital stream to audio is too
power hungry for portable devices. Again, MP3 players show that this
does not have to be so.
>
>
>>>The other links are not SW radios or they need computers to operate or
>>>they are rack mount units that are and will continue to be very
>>>expensive. The rack mounts are not consumer units.
>>>
>>>
>>
>>Once a semiconductor manufacturer produces an ASIC for DRM it will be
>>possible to produce battery operated radios with DRM. A receiver
>>manufacturer could also create a custom ASIC.
>
>
> Yeah that's the no brainer requirement it will take to create a radio
> that will operate on batteries. Make no mistake about this, battery life
> will be shorter than the current generation radios.
>
> So who do you think is going to spend hundreds of thousands of dollars
> to make ASIC's to do this?
Sony could. TI could. Philips could. Analog Devices could. If you could
sell tens of thousands of them, why not. Many companies are making ASICs.
DRM uses MPEG4 AAC audio coding as one of its choices. The Apple IPOD
supports MPEG4 AAC audio coding. Perhaps half the ASIC work is already done.
craigm
>
Chris Mackerell
>
> Well, as the British say "the proof of the pudding is in the eating",
> the best way is to try it yourself.
>
> But, for there are some indications about the possibility on the website
> of Chris Mackerell in New Zealand. He has some interesting audio-samples
> online: http://www.owdjim.gen.nz/chris/radio/DRM/
>
> Including a repport of the number of audio-frames received and the audio
> of it. (the only thing that I find a pitty is that these audio-samples
> have been compress a second time using a lossy codec, creating a "codec
> cascade" effect).
>
>
> There are examples with a lot of packetloss and some with excellent
> reception; some from as far as Europe (20000 km from New-Zealand).
Hi
Thanks for the mention.
I've been watching this thread with interest, but keeping out of the
"debate" :-). When I started putting my DRM recordings on my website
I was on a very expensive internet connection. It's much cheaper
now, and I still have the original .wav files of most of the recordings,
so I might re-encode some of the files at a higher quality.
DRM here has always been very unpredictable, because no-one beams
anything our way. Mind you, the same goes for most major international
broadcasters these days :-(
I understand that RNZI are currently awaiting delivery of a shipment
of Sangean DRM receivers - I'll be interested to see what they are
like.
73 Chris
Frank Dresser
"Tom Holden" <holden...@sympatico.ca> wrote in message
news:4hJYe.11258$0u2.2...@news20.bellglobal.com...
>
[snip]
>
> Moreover, the DRM spectrum is rectangular - even energy distribution. If
we
> take our 10 kHz channel and use SSBc to fill it (carrier at channel edge),
> we will get nearly 10 kHz audio bandwidth. If we also use pre-emphasis (as
> is done in FM), or one of the (ancient) Dolby or dBx type noise reduction
> systems to lift the treble energy in the sideband, we will get a much
> improved S/N. Still very listenable on a conventional DSBAM radio with
> typical IF and AF passbands.
>
> Why don't we hear about this approach? It sounds so easy I think I should
> build a transmitter and experiment with it! There must be a catch...
>
> Tom
>
>
They do use premphasis with AM radio transmissions, at least in the US. The
NRSC has come up with a suggested premphasis scheme:
http://www.nrscstandards.org/Standards/nrsc-1.pdf
This is NRSC 1. As I understand it, NRSC 2 is similiar, but with a a cut
off to the treble boost above some frequency to reduce adjacent channel
interference.
Frank Dresser
Frank Dresser
"Peter Maus" <DPete...@worldnet.att.net> wrote in message
news:n23_e.322504$5N3.2...@bgtnsc05-news.ops.worldnet.att.net...
[snip]
>
> But for now, there is no public clamor for DRM. And absent a
> regulatory mandate, without a public demand there is no motivation for
> implementation.
>
> The market driven future for DRM, and iBiquity, is dim.
Agreed. But DRM might still have long term presence on SW. Some government
which currently subsidizes SW broadcasts to tiny audiences with no certain
benefit might find DRM modulation every bit as good.
As far as IBOC is concerned, I've suspected it's a scheme to get more
broadcast channels on the same license. It seems they're already touting
the extra channels offered by IBOC-FM as a reason to buy an IBOC radio. It
wouldn't surprise me if IBOC AM also has the same capability. If they can
offer some desireable programming on the IBOC sidebands, they might sell a
few radios.
Frank Dresser
Kristoff Bonne
OK. You're message was on the low end of the "queue" for too long. I'll
take some time to reply now.
Tom Holden schreef:
>>Just interested. Does anybody know if the AM-decoding in a "normal price"
>>SW-receiver is done in hardware or in software (ASIC/DSP)?
> I'm not aware of any radios at any price that do AM decoding by DSP. I
> suspect they exist in some form - after all, that is what one would expect
> from Software Defined Radio technology. What about these new DRM radios - do
> they also do AM and FM demodulation via DSP?
Well, I was more thinking in term of ASICs then "generic" DSP-processors.
When I left school (in 1993), I saw the first ASIC-chips (a V21/V23
decoder) which where based on DSP-technology; so I guess these things
must be pretty commonplace now.
If that is the case, a AM-decoder which is also able to do "detect" a
AM-signal is infact SBBc and decode it correct (and not as a "normal"
DSB-AM signal).
Concerning the DRM-chips, if you look at the specification from TI (see
link below, they say that this one chipset can do DAB, DRM, FM, RDS and
AM (plus mp2, mp3 and wma-playback).
So this does look like a SDR but I don't know if it is actually possible
to "flash" the device and upload new DSP-code into it.
The URL is here:
http://focus.ti.com/docs/apps/catalog/tisolutions/tisolutions.jhtml?templateId=938&path=templatedata/cm/general/data/audio_digrad_drm
>>I might have missed something but AFAIK you cannot decode SSBc with a
>>standard AM-radio, can you?
> Yes. I might have the acronym wrong - I mean SSB with reduced carrier, not
> suppressed. The Canadian time signal transmissions from CHU on 3330 and 7335
> kHz use this mode - easily received on the cheapest SW radios.
OK, I understand.
But I've been thinking about this.
It can image that a AM-decoder can decode this correctly for CHU, but I
don't know if this would apply for a broadcasting-signal.
I cannot receive the CHU-signal here (there's a RTTY-like signal ontop
of 3330 Khz and a broadcasting-station on top of 7335 khz) but are there
other signals just below the CHU-signal. (CHU is USB, correct).
I wonder what would happen if you would have a situation like this:
- Say that you have a radio-station in 5 Khz USB SSBc at (say) 7200 Khz
(hence, taking up 7310 to 7315 Khz; just a random frequency)
- and you have a second signal just below (either a SSBc from 7305 to
7310, or a DSB-AM from 7300 to 7310).
How would a AM-decoder react if it was tuned to 7310Khz. Wouldn't he
think this is a DSB-AM station from 7305 to 7315 Khz and completely
decode this incorrectly?
A DSP/ASIC based signal might be programmed to see that the signal at
7305-7310 Khz is completely different then 7310-7315 KHz and switch to
SSBc because of that, but how would an "analog" AM-decoder react to this?
>>DRM has two advantages of this:
>>- it's a digital system. This means it includes features like auxilairy
>>content, "Alternative frequency" information, station identification,
>>multiple streams (e.g. two audio-streams in one DRM transport-stream),
>>variable bandwidth from 4.5 to 20 Khz, variable modulation-sceme and
>>error-correction mechanism based on channel quality, easier support for
>>time- and frequency diversity, single-frequency networking.
> I'm aware of this but it's incompatible with the huge installed base......
True, but I have the impression that the DRM-people where looking for a
digital system to start with.
Broadcast is one of the last areas which are now still analog and there
is a general tendency to migrate to digital.
> ... Frequency diversity and SFN is done with AM.
Frequency-diversity from broadcasting has the advantage that the
meta-information (i.e. the information on what frequency the alternative
signals can be found) is included in the stream itself.
The user does not have to do anything and I think this is a major issue
for the aspect for the user-interface.
Another aspect of frequency-diversity is that in a digital signal, there
is no direct relation anymore between the signal-level at RF-level and
what the listener hears. As long as the signal is good enough to be
decoded, the listener will sound the same thing.
For AM where this is a direct link between the signal-level and the
volume of the signal you hear (or the background noice-level in case you
use AGC), this means that switching between two different frequencies
with different signal-levels will produce a difference in audio-level
for the user.
There is nothing more annoying when you listen to your FM-radio in the
car and that the signal-level (or any other acoustic element) suddenly
changes when the radio switches to an alternative frequency. (it doesn't
happen a lot and when a FM-network is well designed, you will not hear
it), but sometimes it does happen.
Digital broadcasts do not have this problem.
> ... One's sense of hearing does a wonderful job of
> "error correction" as part of an analog system - the digital system can't
> work without its own. Seems like many of the purported advantages are born
> out of necessity.
True, but one of the advantages of a digital system is that the amount
of error-correction can be changed. Groundwave broadcasts has different
characteristics than single-hop broadcasts in a "local" band as does a
multiple hop transmission to the other side of the world.
The better signal you have, the less error-correction is needed and the
more capacity of the transport-stream can be used for actual audio
instead of error-correction bits.
> Auxiliary content, AF, station ID's, multiple streams and various bandwidths
> and bitrates in DAB surely did not excite the public in this country. Now,
> satellite radio with terrestrial fill-ins may be a different matter, and
> cable and satellite DTH audio services with images and text certainly are.
> The takeup has been pretty good.
Over here, these things are now what people have come to expect. They
find it "normal" that they can drive from one side of the country to the
other side with their (FM) car-radio tuned to one station and not having
to do anything. Radio show the stations name for a couple of years now
and as of one or two years, it is also "normal" that the name of the
artist and the song that is playing shows up on their radio-screen.
But, in essence, you are correct. A easy interface is one thing but it
is not the "killer application". It is "content" that drives the market.
If you provide new stations with content that people want to listen to,
than people will switch to new technology. (or just say "OK, I'll take a
that new kind of radio", when they old radio needs replacing, or when
they buy a new car).
So, if DRM allows for new additional stations (like the stations from
RTL), then people will switch.
>>It's easier to integrate into combined DAB/DRM chipsets which allows for
>>an one "integrated" chipset for both systems. It also allows
>>cross-platform services; e.g. does the "AF"-service work between DAB, DRM
>>and FM/RDS.
> This may be of interest in those markets that Eureka 147 DAB was adopted
> with fair market success (where is that other than the UK?) and maybe where
> FM/RDS is likewise deployed but both require that the broadcaster has
> multiple transmitters carrying the same program in multiple modes for the
> listener to realize the benefit of cross-platform AF service. This may be
> more theoretical than practical.
A lot of the large SW-broadcasters do broadcast on multiple frequencies,
don't they?
> ... The time delay for lockup to DRM or DAB is
> so large that AF service using either of them would require dual receivers
> so that the alternate frequency is already tuned and locked before the
> current frequency goes unlocked, rather than blindly chasing the AF list.
I do agree between DRM, DAB and FM, but I would concider this only be
important when you completely lose the signal from one platform. (e.g.
you're driving under a bridge where you do not have a DRM-signal but
where DAB or FM might be OK).
AF between DAB and FM does work OK. When you drive out the coverage-area
of a DAB-transmission, the radio in my car (a FM/DAB radio) will
switch to the same station on FM. (unless you where listening to a
DAB-only station of course).
This switch-over can also happen tempory. E.g. your tuned to a
"national" station on DAB, it is possible that the "TA" (traffic
announcement) information inside the DAB-stream will make your radio
switch to a local FM-frequency for the traffic-information and then
switch back to the national DAB-station afterwards.
>>- it's one technology for LW/MW, for SW, for 11 meter "local" broadcasting
>>and, with the extension of DRM+, for band I and band II.
> So could SSBc and maybe NBFM
Well, the goal would be to digitise the radiostation now on FM.
Switching to another analog mode would (IMHO) not be concidered an option.
>>- And it allows you to lower the transmission-power (and hence the
>>electrivity-bill).
> My observations of DRM on shortwave has been that high transmitter power is
> still needed - maybe less than for DSBAM. SSBc also saves power.
True, but I don't know if SSBc is a real option (see above).
Concerning transmission-power, one of the examples is the BBC
worldservice for Europe on MW here. They broadcast in AM on 648 Khz with
The DRM-broadcast at 1296 Khz is 70 KW (and also 500 KW when
broadcasting in AM at that frequency).
>>Interest idea. Just interested to know how 10 Khz SSBc would react to
>>selective fading. As you said in the beginning, the problem is when the
>>carrier is gone. Wouldn't you have the same problem as with a
>>DSBAM-receiver?
> When selective fade knocks out the carrier, you lose lock but not the
> modulation, with a "true" synchronous AM detector. There will be an error
> distortion, as in asynchronous ECSS, which could be very small for some
> considerable time. DRM is not immune to selective fading - the cause is
> multipath which causes jitter or spreading of the digital stream and when it
> is big enough - no decoding and then wait for re-lock after the jitter has
> fallen below the acceptable threshold.
Well, it's not really imune, but it is less influenced by it. Selective
fading influences parts of the spectrum and you should remember that a
DRM-signal concist of a large number small carriers one next to another.
Selective fading influences only a number of carriers, but not all of
them at the same time.
As the bits of the transport-stream are first "scrambled" before being
spread out over the different carriers (and "descrambled" at the
receiver-side), this means that the errors due to the selective
fading-will also be "spread out", and that's where the error-correction
techniques come in.
So, yes, selective fading does have an effect, but there due to the way
digital broadcasting works, these effects will be partly countered.
I'm sorry but I have to stop now. (yes, I have a life outside the
internet too. :-) ). I'll reply to the last part later.
Just a small reply.
> How does DRM react to overlapping spectrum from an adjacent or co-DRM? Not
> likely very well given its poor performance in the presence of DSBAM or SSB
> overlapping its spectrum.
True!
And that's one of the issues I see with DRM. If it would become
successfull, it would increase competition for frequencies in the
SW-band which hasn't existed for the last couple of years. (as every was
then leaving the SW-bands).
BTW. Something I found yesterday. The website of the British version of
"radio Luxembourg".
http://www.radioluxembourg.co.uk/about-history.htm
See the bottom part:
"2005…. The legend is back ! RTL Group is using the DRM technology to
re-launch Radio Luxembourg on 7145 kHz. New generation digital radio
receivers featuring DRM/DAB/FM/AM will be available by the end of the
year from various manufacturers, for a perfect tune in to Radio
Luxembourg. RTL Group is actively supporting the digitalradioDR
initiative. www.digitalradiodr.com and www.rtlgroup.com/drm"
So, besides the MW and LW-frequencies I posted here before for Germany,
France, Belgium and the Netherlands, this is another frequency: 7145 Khz
for their broadcasts aimed at the UK!
> Tom
Cheerio! Kr. Bone.
dxAce
Kristoff Bonne wrote:
[Massive amount of DRM crap snipped]
DRM = QRM
dxAce
Michigan
USA
Tom Holden
news:pjc_e.84714$qY1....@bgtnsc04-news.ops.worldnet.att.net...
>
> "Tom Holden" <holden...@sympatico.ca> wrote in message
> news:4hJYe.11258$0u2.2...@news20.bellglobal.com...
>>
> [snip]
>
>>
>> Moreover, the DRM spectrum is rectangular - even energy distribution. If
> we
>> take our 10 kHz channel and use SSBc to fill it (carrier at channel
>> edge),
>> we will get nearly 10 kHz audio bandwidth. If we also use pre-emphasis
>> (as
>> is done in FM), or one of the (ancient) Dolby or dBx type noise reduction
>> systems to lift the treble energy in the sideband, we will get a much
>> improved S/N. Still very listenable on a conventional DSBAM radio with
>> typical IF and AF passbands.
>
> The
> NRSC has come up with a suggested premphasis scheme:
>
> http://www.nrscstandards.org/Standards/nrsc-1.pdf
>
> This is NRSC 1. As I understand it, NRSC 2 is similiar, but with a a cut
> off to the treble boost above some frequency to reduce adjacent channel
> interference.
>
> Frank Dresser
>
pre-/de-emphasis curve that would be a workable compromise between the ideal
for best S/N that could be achieved with new radios and listenability on
typical radios. Of course, with a new standard implemented in new radios,
one could use double-ended multi-band companding for greater benefit.
Tom
Tom Holden
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
news:4339b241$0$25588$ba62...@news.skynet.be...
> Tom Holden schreef:
>>>Just interested. Does anybody know if the AM-decoding in a "normal price"
>>>SW-receiver is done in hardware or in software (ASIC/DSP)?
>
>> I'm not aware of any radios at any price that do AM decoding by DSP. I
>> suspect they exist in some form - after all, that is what one would
>> expect from Software Defined Radio technology. What about these new DRM
>> radios - do they also do AM and FM demodulation via DSP?
>
> Well, I was more thinking in term of ASICs then "generic" DSP-processors.
Whether general-purpose DSP or ASIC DSP or software DSP running on a general
purpose CPU, it's still DSP.
>
> When I left school (in 1993), I saw the first ASIC-chips (a V21/V23
> decoder) which where based on DSP-technology; so I guess these things must
> be pretty commonplace now.
> If that is the case, a AM-decoder which is also able to do "detect" a
> AM-signal is infact SBBc and decode it correct (and not as a "normal"
> DSB-AM signal).
It's called a synchronous AM detector. While not commonplace, it is included
in several 'better' receivers. AM Stereo receivers used sync AM detectors.
The Sony IC-2010 has a highly reputed sync AM IC - analog. The WinRadio line
looks to include both sync AM and conventional envelope detectors in the
software DSP that runs on the PC to demodulate the 12 kHz IF output fed into
the PC sound system. Any sync AM detector is capable of demodulating both
DSB-AM with carrier and SSBc AM. As it is a product detector with a
synchronised BFO, the same detector may also be used for SSB suppressed
carrier and other modes, especially by defeating the synchroniser.
> Concerning the DRM-chips, if you look at the specification from TI (see
> link below, they say that this one chipset can do DAB, DRM, FM, RDS and AM
> (plus mp2, mp3 and wma-playback).
>
> So this does look like a SDR but I don't know if it is actually possible
> to "flash" the device and upload new DSP-code into it.
The Radioscape module based on this chipset can be programmed via USB. It
looks to incorporate AM envelope detection as standard.
Regards,
Tom
Tom Holden
"Kristoff Bonne" <compaq...@kristoff.bonne> wrote in message
news:4339b241$0$25588$ba62...@news.skynet.be...
>
> don't know if this would apply for a broadcasting-signal.
Why not? CHU contains human voice announcements in USBc so why would a SSBc
broadcast signal be any different as far as an envelope detector is
concerned?
> I wonder what would happen if you would have a situation like this:
> - Say that you have a radio-station in 5 Khz USB SSBc at (say) 7200 Khz
> (hence, taking up 7310 to 7315 Khz; just a random frequency)
(you mean the 5 kHz USBc carrier is at 7310, not 7200)
> - and you have a second signal just below (either a SSBc from 7305 to
> 7310, or a DSB-AM from 7300 to 7310).
(i.e. a USBc or a DSBC at 7305)
>
> How would a AM-decoder react if it was tuned to 7310Khz. Wouldn't he think
> this is a DSB-AM station from 7305 to 7315 Khz and completely decode this
> incorrectly?
If the IF shifts the 7310 to the centre of its 5 kHz passband, then both an
envelope detector or a sync AM detector centred in the passband are going to
see the upper 2.5k of the upper sideband of the lower adjacent freq. As you
tune the receiver higher in frequency, less of the undesired sideband and
more of the desired will be seen, thus improving the S/I. A correctly
designed selectable sideband synch AM receiver would correctly align the
passband on the selected sideband and with the synchronous BFO.
> A DSP/ASIC based signal might be programmed to see that the signal at
> 7305-7310 Khz is completely different then 7310-7315 KHz and switch to
> SSBc because of that, but how would an "analog" AM-decoder react to this?
Because sync AM has a lock-in time or latency, it might be desirable to use
envelope detection for rapid and coarse tuning with an optional automatic
switch to sync AM mode. Of course, a DXer would want to exercise manual
control. I have no idea whether such auto switching is realisable in any
practical way.
I'm replying in digestible chunks - more later!
73, Tom
Telamon
"Tom Holden" <holden...@sympatico.ca> wrote:
Yeah Tom I post the links. Both links are the same radio. This is the
one DRM SW radio I have been able to find. This is the ONE concept radio
by two of the companies involved in the DRM consortium.
--
Telamon
Ventura, California
Telamon
craigm <no...@domain.invalid> wrote:
> Telamon wrote:
> > In article <cWRZe.21962$X6.1...@fe05.lga>,
> > craigm <no...@domain.invalid> wrote:
> >
> >
> >>Telamon wrote:
> >>
> >>
> >>>>>The statements that I have seen before about DRM being an open standard
> >>>>>are as far as I see false because the software is not in the public
> >>>>>domain.
>
> The software does not have to be in the public domain for the standard
> to be open. The standard is one thing, the software is an implementation
> of the standard. I can write software that complies with an open
> standard and sell it without putting the source in the public domain.
The DRM standard in part uses proprietary code licensed by several
companies depend on the mode you operate in. That does not meet the open
requirement.
> >>>>Like this one?
> >>>>http://sourceforge.net/projects/drm/
> >>>
> >>>
> >>>No I don't like it. This is another computer - radio. You do realize
> >>>that most of these units need a computer to operate? These are not stand
> >>>alone radios. The link I provided is the one stand alone SW radio that I
> >>>know about.
> >>>
> >>
> >>The reply was in response to your statement that the software was not in
> >>public domain. Source code is available so your argument fails.
> >
> >
> > You do not have the rights to the software, those rights are reserved.
> > For the time being you can down load and compile it on a local machine
> > for your own use. If the rights holder tell you to stop using it then
> > that's it.
>
> If you follow the requirements of the GPL, then the rights holder won't
> tell you to stop using it.
>
>
> If money is demanded then you will have to pay it.
> Per the GPL, any money is for distribution costs. Since the links were
> for a free download site, there is no cost, now or in the furute.
>
>
> There are
> > many ways this can be enforced.
>
> Yes, but you would have to violate the terms of the GPL.
I don't know what you are talking about here. This software is being
sold and is not free. If there is a free DRM radio decoder I did not
know about it. I don't understand how this could be because some of the
encoding/decoding algorithms are not free. Please point to the free DRM
decoding software.
You are missing about every point in the thread. The DRM Troll started
out saying that the DRM SW was imminent because consumer radios existed.
There is one that I can find no thanks to the Troll. I don't know if
this one radio is actually being sold since it is described as a
"concept radio." He kept posting links of the same radios that are not
SW radios but are AMBCB or FM. The radios that did receive SW need a
computer to operate or they were very expensive professional rack mount
units. Basically the radios that need a computer are science experiments
for early adopters. There is no analog equivalent DRM SW radio being
manufactured today as far as I can tell.
Of course there could be a DRM SW equivalent tomorrow. Of course any
company with the resources could spend the money to produce ASIC's to do
the job. It is just that they haven't done it yet contrary to what the
DRM Troll is espousing.
A DRM radio needs to perform many functions compared to what an MP3
player needs to do. Additional functions over what an analog radio
requires so even if a well financed company decided to build a high
order of integration with several ASIC's a DRM radio would still draw
much more power than a analog radio. Standard batteries many not be able
to handle the power requirements and when DRM SW portables show up they
will probably use lithium ion rechargeable batteries.
There is nothing magical about DRM technology. Everything used by the
DRM scheme is used someplace else. Nothing new here and that might be
part of the problem of a technology not well matched to the SW
propagation environment.
--
Telamon
Ventura, California
Michael A. Terrell
>
> You are missing about every point in the thread. The DRM Troll started
> out saying that the DRM SW was imminent because consumer radios existed.
> There is one that I can find no thanks to the Troll. I don't know if
> this one radio is actually being sold since it is described as a
> "concept radio." He kept posting links of the same radios that are not
> SW radios but are AMBCB or FM. The radios that did receive SW need a
> computer to operate or they were very expensive professional rack mount
> units. Basically the radios that need a computer are science experiments
> for early adopters. There is no analog equivalent DRM SW radio being
> manufactured today as far as I can tell.
>
> Telamon
> Ventura, California
A "Concept" unit is usually something that was built to take to trade
shows to see if there is a market for a product. With radios its not
uncommon for the "Concept" device to only have a computer board and
software to let you operate the controls. I saw one that cost a company
over $1,000,000 US dollars. It had a laptop inside, and a bunch of 50
Ohm 2 Watt carbon resistors across all of the BNC connectors, in case
someone actually tried to hook it up. The real prototype DSP based
telemetry receiver was still on the designers bench, not working.
--
?
Michael A. Terrell
Central Florida