Radio London RSL, why 1 Watt?
Stephen
which is on the air for today's anniversary of the day Radio London and the
other "pirate radio ships" closed down in 1967. This is of course because
the transmitter power is only 1 Watt. But FM RSL's have 50 Watts, and the
normal minimum power for a small local radio station on AM is 100 Watts. As
far as I know, 1 Watt would provide a normal strength signal over a range of
only a few hundred yards. It hardly seems worth the cost of the license!
Wouldn't 50 or 100 Watts be more sensible ? (It would also mean I would
stand some chance of hearing the Radio London RSL.) Does anyone know why AM
RSL's are restricted to as little as 1 Watt ?
Paul Martin
Stephen wrote:
> other "pirate radio ships" closed down in 1967. This is of course because
> the transmitter power is only 1 Watt. But FM RSL's have 50 Watts, and the
No, VHF FM RSLs are licenced at 10W, and exceptionally 20W.
1W AM on Medium Wave will get you about 5 miles, assuming you have a
good earth on the sending aerial. The problem in London is the sheer
number and density of buildings.
Radio 4 MW Lots Road has always been a difficult catch, unless you're
very close to it.
--
Paul Martin <p...@zetnet.net>
Mark Carver
"Paul Martin" <p...@zetnet.net> wrote in message
news:slrn9nhv...@manlap.zetnet.co.uk...
>
> Radio 4 MW Lots Road has always been a difficult catch, unless you're
> very close to it.
Agreed, as was LBC from the same site, frequency (719/720kHz),
and output power ?? 1973-75.
However Capital who were on 557 kHz from the same site could be heard
over most of S.E. England. Anyone know the reason ? 557kHz is not *that* much
lower in freq than 719kHz
cashaw
>
> Radio 4 MW Lots Road has always been a difficult catch, unless you're
> very close to it.
I've never understood the reason for R4 Lots Road, who is it's intended
audience ? LW travels much better to Northern Europe and is not as
liable to being swamped in the evening.
Clive.
Richard Bentley
In the 1960's when the pirate radio stations were at their height, I
built a sensitive valve radio receiver with 3 IF stages! It also had a
noise clipper circuit to clip any interference. On local stations, it
produced over 20 Volts of AGC!
In the North of England, with along aerial I could drag in almost all
the pirate stations as listed below:
Radio Wavelength Power
270 270 m
390 390 m
Britain 355 m 10 kW
Caroline N. 199 m 20 kW
Caroline S. 259 m 50 kW
City 299 m
England 227 m 55-110 kW
Essex 222 m
London 266 m 75 kW
Scotland 242 m
Ones I couldn't receive:
Radio Wavelength
Invicta 306 m
Manx 232 m
Tower 234 m
Most of these stations were really great to listen to. I don't think
that any of today's stations are as good in their music mix or format.
Or is it just me?
Cheers,
Richard
Mr R@t / Alex - J10 [2.33za]
news:997779964.7325.0.nnrp-
stand some chance of hearing the Radio London RSL.) Does anyone know why AM
> RSL's are restricted to as little as 1 Watt ?
last time I read the RSL licenses [about 6 years ago] , the
radiocommunications agency claimed that higher powers meant dangerous
voltages could appear on the antenna array so this was allegedly done for
safety reasons.
I don't know why they could not have allowed larger powers but said the
engineer must have passed the RAE? After all I'm sure this is part of the
exam - indeed amateurs seem allowed to use far greater powers on similar
bands. Would give a boost maybe to amateur radio , improve the amateurs'
with other community groups [as well as stuff like raynet] and give 'em
something else constructive to do :)
Alex [considering RAE]
--
Alex / Mr R@t - Junk-Chun 10 Sound System, Reading
attention: headers are munged to avoid spam
correct e:mail is : <golf><romeo><tango>23<AT>ratcotel<DOT>net
network23 reading: http://www.ratsnest23.org
Tony Sayer
Alex - J10 [2.33za] <gr...@spam-nyet.sssr.su> stuck his oar in and spake
thus
A while ago since I did anything with RSL's and VHF ones at that isn't
the power set by the licence fee scale charges/costs?.
BTW the 1 watt job from London was receivable on the M11 at Stansted
this AM lost it on the way back to Cambridge, but I have heard it on a
tuner with an outside wire in Camb not bad for a watt!...
--
Tony Sayer
Bancom Communications Ltd U.K. Tel +44 1223 566577 Fax +44 1223 566588
P.O. Box 280, Cambridge, England, CB2 2DY E-Mail to...@bancom.co.uk
TL447-553 52* 10.57'N 0* 6.96 E
Marcus Durham
<ste...@junkmailblocker.sptv.demon.co.uk> shared the following with us
in uk.tech.broadcast:
[snip]
>But FM RSL's have 50 Watts,
25 watts max as standard but there are lower limits for London.
As for the AM restrictions, I was once told that the limit was low
because of electrical risks with the transmitting aerials at higher
power.
--
Marcus Durham
"It's To Do With You!"
www.mdurham.co.uk
Dave Cole
To keep the MP's happy was one theory I heard but the real reason was
poor reception of long wave in the city due to the large steel framed
buildings.
Tim
Stephen wrote in message
<997779964.7325.0...@news.demon.co.uk>...
than 25W FM (which is the maximum allowed for an RSL on FM - although most
RLs will only be allocated 10W, and in London all will get 10W.)
There is an argument that AM RSLs should only get 0.25W - because higher
power levels through an AM aerial system are actually quite dangerous.
Martin Griffith
<mark....@gmx.net> scribbled:
>
>"Paul Martin" <p...@zetnet.net> wrote in message
>news:slrn9nhv...@manlap.zetnet.co.uk...
>>
>> Radio 4 MW Lots Road has always been a difficult catch, unless you're
>> very close to it.
>
>Agreed, as was LBC from the same site, frequency (719/720kHz),
>and output power ?? 1973-75.
>
>However Capital who were on 557 kHz from the same site could be heard
>over most of S.E. England. Anyone know the reason ?
we used to get many reception reports from Italy, and other parts of
S E Europe and Southern Africa when Crapital was on 539(still got the
T shirt), it was a brilliant place to work in those days, with Gerry
O'Reillly as chief eng.
Not being a RF guy, i can't comment on why 539('ting) was so good
>
>
Martin
Windoze... from the people that brought you Edlin.
Stephen
"Tim" <tim_u...@tim-gray.org.uk> wrote in message
news:3b798...@mk-nntp-1.news.uk.worldonline.com...
95.8 FM on any FM radio with no trouble at all when I visit Reading, 50
miles out of London, even though the erp is only 2kW (in either plane of
polarisation). The reception of AM stations from London, such as Ritz 1035
with 1kW is far worse. There is another factor in cities, which is standing
waves between steel framed buildings, and people like myself using radios
within a steel framed building. Although my flat is in London, one of
London's AM local stations is so under powered that I just can't get
satisfactory reception indoors no matter what I do. This is Premier. In my
experience AM needs more power than FM, particularly when you are trying to
serve a built up area with low ground conductivity and steel framed
buildings. As for safety problems with high aerial voltage, surely there
could be another way round this. A safety inspection for example, to ensure
that there is no public access to the aerial, and it is fenced off or behind
a locked gate etc. Since the aerial current should be no higher than the
sort of currents found in domestic electrical wiring, it should also be
possible to improve safety by specifying insulated wire for the aerial.
Ashley Booth
The wire being insulated will not make it safe. You can still get RF
burns and they are painful!
--
Ashley Booth
ICQ 74 74 32 33 www.snglinks.com
"This is not a pipe: '|' "
Philip de Cadanet
>> > >Even though I am in London, I can't hear the "Radio London" RSL on
>1134
You may wish to try one other AM RSL on 531KHz broadcasting near the
M25/M23 junction. They can be comfortably heard over London and much of
the home counties during daylight hours when groundwave coverage in
relatively good.
> This is of course
>because
>> > >the transmitter power is only 1 Watt.
Transmitter power on 531 is in the region of 100W. The fact that one is
restricted in antenna height to 20m thereby restricts gain. I believe it
is this fact that to get 1W 'ERP' one can get away with running much
more power. 50-100W is actually quite typical for an AM RSL operation.
> But FM RSL's have 50 Watts,
You're very fortunate if the authority's allow you 50W RF out on FM!
>and the
>> > >normal minimum power for a small local radio station on AM is 100
>Watts.
>> As
>> > >far as I know, 1 Watt would provide a normal strength signal over a
>range
>> > of
>> > >only a few hundred yards. It hardly seems worth the cost of the
>license!
To my knowledge few RSL's make a profit.
>> > >Wouldn't 50 or 100 Watts be more sensible ? (It would also mean I
>would
>> > >stand some chance of hearing the Radio London RSL.) Does anyone
>know why
>> AM
>> > >RSL's are restricted to as little as 1 Watt ?
Explained above.
>> > There is an argument that AM RSLs should only get 0.25W - because
>higher
>> > power levels through an AM aerial system are actually quite
>dangerous.
Who's argument?
>> >
>> I think the idea of AM needing less power is erroneous. I can hear
>Capital
>> 95.8 FM on any FM radio with no trouble at all when I visit Reading,
>50
>> miles out of London, even though the erp is only 2kW (in either plane
>of
>> polarisation). The reception of AM stations from London, such as Ritz
>1035
>> with 1kW is far worse.
Poor ground I imagine. It's called a long wire at Crystal Palace. How
much worse could you get for a suitable AM ground system!
> There is another factor in cities, which is
>standing
>> waves between steel framed buildings, and people like myself using
>radios
>> within a steel framed building. Although my flat is in London, one of
>> London's AM local stations is so under powered that I just can't get
>> satisfactory reception indoors no matter what I do. This is Premier.
>In my
>> experience AM needs more power than FM, particularly when you are
>trying to
>> serve a built up area with low ground conductivity and steel framed
>> buildings. As for safety problems with high aerial voltage, surely
>there
>> could be another way round this. A safety inspection for example, to
>ensure
>> that there is no public access to the aerial, and it is fenced off or
>behind
>> a locked gate etc. Since the aerial current should be no higher than
>the
>> sort of currents found in domestic electrical wiring, it should also
>be
>> possible to improve safety by specifying insulated wire for the
>aerial.
FYI Capaital AM have a directional array at Saffren Green and have good
coverage indeed to the south. You want to try and listen to the north
but a few miles!
Philip de Cadenet
S Whitt
"Tony Sayer" <tony@bancom_nilspamus_.co.uk> wrote in message
news:S7YHARBh...@bancom.co.uk...
> BTW the 1 watt job from London was receivable on the M11 at Stansted
> this AM lost it on the way back to Cambridge, but I have heard it on a
> tuner with an outside wire in Camb not bad for a watt!...
> --
If you think that's not bad for 1watt check out Medium Wave News Volume 47/3
(July Aug 2001) which includes a list of long distance reception of 1 watt
RSL/LPAM stations.
Perhaps most impressive was Waves AM from Peterhead Scotland with 50mW heard
512km away in Norway. Summertime 1994 & daytime!
Numerous logs of RSLs have been made between 200-400km where a large part of
the path has been over the sea; especially from RNI/R London R Caroline.
These ones are heard as far as the German border.
Remember these are all daytime ground wave signals.
Now here's a challenge: Check out Susy Radio on 531kHz to see how a low
frequency helps. this RSL is running now, through August. I've heard it
250km north of the station's location in Surrey.
It's an easy catch on a car radio at 50km.
rgds
Steve Whitt
more info on Medium Wave News visit www.mwcircle.org
Nick Jeffery
news:9lmk25$ghd$1...@plutonium.btinternet.com...
> Now here's a challenge: Check out Susy Radio on 531kHz to see how a low
> frequency helps. this RSL is running now, through August. I've heard it
> 250km north of the station's location in Surrey.
Aye.
Check out Tom Brook's jingles/VO's. I did those. That's me. Woo! ;)
Nick.