Power Line Carrier tranceivers
Stevec
are no obsolete.
Can anybody suggest a replacement even if not compatable.
Thanx in anticipation.
Steve.
stevec...@iafrica.com
Christer Johansson
"Stevec" <ste...@iafrica.com> wrote:
>National used to make the LM2893 carrier-current tranceivers, however thy
>are no obsolete.
>Can anybody suggest a replacement even if not compatable.
Take a look at our PLM-24 Power Line Modem, it may fit your needs?
See http://www.hth.com/plm-24/ or drop me an e-mail for more info.
Regards,
/Christer
[NOTE: Clear the "X" from my e-mail address if you want to e-mail me]
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
* High Tech Horizon - Christer Johansson - E-mail: c...@hth.com *
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Send _AND_ receive serial data over the power lines. For more info
about the PLM-24 Power Line Modem go to http://www.hth.com/plm-24/
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
ibag...@bagotronix.com
>National used to make the LM2893 carrier-current tranceivers, however thy
>are no obsolete.
>Can anybody suggest a replacement even if not compatable.
>Thanx in anticipation.
>Steve.
>stevec...@iafrica.com
>
>
Try Intellon. They have a website - www.intellon.com or something
like that.
Ivan
Don Yuniskis
> >National used to make the LM2893 carrier-current tranceivers, however thy
> >are no obsolete.
Hmmm... presumably the 1893 is also gone?
Have you looked at Signetics' NE5050? (ASK vs. FSK encoding)
> >Can anybody suggest a replacement even if not compatable.
> >Thanx in anticipation.
BTW, anyone know what ever became of "GridComm"? They supposedly
had a pretty robust product...
--don
[return address mangled]
Mike Albaugh
it piqued my curiosity...
Don Yuniskis (d...@cutout.gci-net.com) wrote:
: > On 13 Aug 1998 16:03:32 GMT, "Stevec" <ste...@iafrica.com> wrote:
: > >National used to make the LM2893 carrier-current tranceivers, however thy
: > >are no obsolete.
: Hmmm... presumably the 1893 is also gone?
: Have you looked at Signetics' NE5050? (ASK vs. FSK encoding)
Some years ago, there was an article in H.P. Technical
Journal about experiments with spread-spectrum on A.C. line.
Really clever hack using essentially auto-correlation and
LFSRs to send 100+kbps. Don't know what happened to it or
why, but I suspect that somebody got the gummint involved
and got it outlawed.
The only other things I've seen were both low-speed
and _fiendishly_ expensive. I had been interested in using
them for machine-status info back to a central location without
stringing more wire, and the salesdroid enthusiastically
pointed out that they were used in _exactly_ that application
by another customer. Turns out that the "other customer" was
the U.S. Postal service, who found it a lot cheaper to use
them than to get permission to drill a hole in the marble
and granite walls of various public buildings. With a client
like that, they saw no need to make them cost-effective to
mre mortals... :-)
(How slow and how expensive? well, we ended up using a
1200-bps-on-a-good-day-with-a-tailwind cell-modem instead...)
Mike
| alb...@agames.com, speaking only for myself
Don Yuniskis
> For me, this is one of those "casual interest" things, but
> it piqued my curiosity...
> Some years ago, there was an article in H.P. Technical
> Journal about experiments with spread-spectrum on A.C. line.
> Really clever hack using essentially auto-correlation and
> LFSRs to send 100+kbps. Don't know what happened to it or
> why, but I suspect that somebody got the gummint involved
> and got it outlawed.
Hmmm, interesting. Though, arguably, I can see why they would
want to clean up the AC mains in that case...
> The only other things I've seen were both low-speed
> and _fiendishly_ expensive. I had been interested in using
> them for machine-status info back to a central location without
> stringing more wire, and the salesdroid enthusiastically
> pointed out that they were used in _exactly_ that application
> by another customer. Turns out that the "other customer" was
> the U.S. Postal service, who found it a lot cheaper to use
> them than to get permission to drill a hole in the marble
> and granite walls of various public buildings. With a client
> like that, they saw no need to make them cost-effective to
> mre mortals... :-)
> (How slow and how expensive? well, we ended up using a
> 1200-bps-on-a-good-day-with-a-tailwind cell-modem instead...)
You can do a bit better than that without really trying very hard with
a 2893 -- heck, you can even use it to push *audio* down the mains!
Higher bit rates require a bit more engineering in the filters,
etc. (and, usually synchronization to the mains, etc. to help
improve throughput).
The GridComm device I mentioned previously would "reliably" do
38Kbaud. It used several modulation schemes concurrently and
took care of all the error correcting, etc.
Of course, since it looked like a "good" product, the company
*must* have gone out of business...
--don
[return address mangled]
Robert McConnell
>
>> Some years ago, there was an article in H.P. Technical
>>Journal about experiments with spread-spectrum on A.C. line.
>>Really clever hack using essentially auto-correlation and
>>LFSRs to send 100+kbps. Don't know what happened to it or
>>why, but I suspect that somebody got the gummint involved
>>and got it outlawed.
>
>I can't see how this could be outlawed, unless one was transmitting
>with frequencies / powers outside those permitted.
>
>This same argument comes up with regard to modulating the switching
>frequency and/or pulse width in switching power supplies, or
>FM-modulating the CPU clock in PCs and general embedded products - the
>aim being to reduce the *measured* emissions. This sort of thing
>CANNOT in the general case be outlawed because there are so many
>things which *naturally* cause variations in the emitted spectrum;
>e.g. the CPU executing different parts of its firmware.
>
>Certainly one could do the same thing in AC line data transfer as
>already happens in every normal modem: use increasingly clever
>modulation schemes. I have not looked at this for some years but I
>suspect that most present-day AC line comms chips use the same very
>simple FSK-based schemes which they used to.
There are some FCC defined limits on the power levels you can use,
mostly to prevent the signals from escaping into the air and
interfering with other equipment. Beyond that, there are practical
limits to bandwidth vs. range and significant noise problems to be
overcome. Then there is the problem of bridging between the two or
three phases in the common power wiring schemes, plus bridging around
any transformers if you want to talk between buildings. Isolating your
sensitive RF circuits from the AC voltages, power spikes and surges is
another non-trivial exercise.
There are several systems that provide solutions for some of these
problems, including X10 and Echelon's LonTalk. LonTalk only supports
9600bps over powerline, even with the new spread spectrum
transceivers, and they won't guarantee that it works. You have to buy
a pair of test units and run periodic performance tests onsite as part
of the support and maintenance agreement.
Bob McConnell
N2SPP
Ric
interest.
Rick Miller
Attached please find what is currently available. Pricing will be $15
in small quantities and $12 in large quantities. Regards. Eitan
Einwohner
_____________________________________________
ITM1- 1.5 Mbps DCSK Power Line Transceiver
- 1.5 Mbps max throughput
- Enables high speed LANs over AC power lines
- Utilizes DCSK technology
- Low cost component
General Description
ITRAN's ITM1 component, based on its patent pending DCSK technology,
employs the same technology as ITRAN's IT5000 and IT800 CEBus®
compatible chips. Using these components as a design basis, ITRAN
engineers have successfully implemented DCSK in a broadband throughput
range. The ITM1, delivering 1.5 Mbps of speed over residential power
lines, is the ideal component for SOHO, high speed Internet, telephony,
and utility access applications.
High Bit Rate Power Line Networks
The ITM1 enables1.5 Mbps communications over existing electrical
wiring. Thus, the replacement of dedicated cable LANs with existing
electrical wiring is transparent to the end user. The ITM1 modulates a
variety of networking applications onto the power line carrier, enabling
file transfer, print sharing and many other networking applications
without changing existing software. Employing ITRAN's ITM1, home and
small business owners will no loner have to tear through walls or pay
for coaxial cablei n order to network. ITRAN's ITM1 power line modem
greatly reduces the real cost of home networking.
Utility Access Technology
ITRAN's ITM1 is the ideal power line modem for utility companies looking
to provide communications services to their customers. With its 1.5Mpbs
throughput and packet switching CSMA protocol, the ITM1 allows electric
companies to transfer the Internet and other data streams at many times
the bit rate of alternative technologies. Employing the ITM1, utilities
can distribute data from the transformer through the meter and to every
electrical outlet of their customers' homes.
Low Cost Component
Despite its high sophistication, the DCSK based ITM1 is simple in design
and inexpensive to produce. Although it greatly outperforms competing
ICs, the ITM1 is only a fraction of the cost of other high throughput
power line carrier chips. The ITM1 can thus be inexpensively integrated
into Ethernet compatible network interface cards and into utility access
and communications systems.
____________________________________
Ric wrote:
> I was wondering what it would take to obtain data sheets and
> any application notes on your ITM1.
>
> And pricing?
>
> Thanks
> Rick Miller
--
Eitan Einwohner
North American Marketing Manager
ei...@itrancomm.com
ITRAN Communications Ltd.
West Coast Office
Tel: 415-643-6240
Fax: 415-643-6235
http://www.itrancomm.com
Kerry Morris
net.com> writes
>> >National used to make the LM2893 carrier-current tranceivers, however thy
>> >are no obsolete.
>
>Hmmm... presumably the 1893 is also gone?
>
>Have you looked at Signetics' NE5050? (ASK vs. FSK encoding)
>
Also obsolete, I think, but for a modern ASK PLC device, try the Philips
TDA5051 - nice and simple to interface to the power line, with digital
waveform generation and filtering.
It is designed to be compliant with EN50065, for consumer 'C' band
applications in the frequency range 125-140 kHz, but by using an
appropriate clock frequency (7.68MHz), it could even be used as the
basis for a homebrew X-10 design! :)
Another recent device in a similar vein is the SGS-Thomson ST7537HS1.
This is a narrow-band FSK device, with not quite the same level of on-
chip integration as the TDA5051, but again designed to be compliant with
EN50065 'C' band.
Regards,
--
Kerry Morris