"Richard Crowley" writes:
"David Nebenzahl" wrote ...
Richard Crowley spake thus:
"Bikedrd" wrote ...
What I am wondering is: is there a way to use the single speaker wire
pair to transmit line-level RCA audio output from my satellite
receiver to an input on my amp?
Do you have digital audio output on the satellite receiver?
(Either an SPDIF optical port or an orange RCA jack.)
And a digital input on your receiver? You could make the
digital signal into a super-balanced feed and receive it with a
balanced digital receiver on the other end. It wouldn't require
shielding OR ground reference.
You would need to do some experimenting to discover the
impedance of the speaker wire, and likely hack together a
little 1-chip circuit at each end. But this is a common solution
and there are ample application diagrams for the circuit.
Do you happen to have any links to such diagrams handy? I'm curious about
this as well.
Look at the application circuits for high-speed differential
drivers like Maxim MAX4447, 4448, 4449 and the
corresponding recivers like Maxim MAX4144, 4145.
There are many similar products from Maxim and others.
If they can send video over twisted pair phone wiring, they
can surely send digital audio over an old ratty speaker pair.
Yes. One idea that coudl be worth of try is to check if some
ready made cheap video to UPD adapter would work on the conversion.
The S/PDIF signal is 75 ohms and on same frequency and signal level
range as video signals, so a video balun would be a good match
for converting spdif to balanced signal and back.
For that matter, there are ICs and circuits specifically for
driving 110-ohm twisted pair AES/EBU audio. Those
could likely be pressed into service for something like this.
The driver and receiver for 110-owh AES/EBU is practically
same as used in RS-485. So check the RS-485 component for this.
Some SPDIF information and related circuits can be found at
http://www.epanorama.net/documents/audio/spdif.html
--
Tomi Engdahl (
http://www.iki.fi/then/)
Take a look at my electronics web links and documents at
http://www.epanorama.net/