On Wed, 6 Oct 2004 11:45:27 -0500, Mark Zenier wrote
(in article ):

In article ,
tech guy wrote:
Some tv stations broadcast audio programming on their second audio
channel (SAP). For example, some channels play the news in Spanish.

Is there any way to listen to these second audio programs on the
radio?
If I have a cheap digital tuning (or analog tuning) AM / FM radio,
is there a way to let it pick up the SAP frequencies?

Step by step instructions would be greatly appreciated.

This is for US analog TV.

SAP is a narrowband FM subcarrier on the TV Audio Signal. 75 Khz,
I think. So if you tap the detector output of a TV set [Note: Extreme
shock hazard on most TV Sets] or a VCR, and feed that into a receiver
or VLF converter, you can pick it up (poorly) using slope detection
on an AM receiver. It's very narrowband FM, and uses one of the noise
reduction systems (dbx? dolby?). There's also a "studio to remote"
subcarrier at, I think, 95 kHz. (I never got around to monitoring it).

This is the same as a SCA signal on a FM Audio Broadcast, where
67, 75, and 92 kHz are used for "Elevator Music", talking newspapers
for the blind, and various subscription ethnic radio services.

Easiest way would be to hit the thrift stores or repair shops for
a half-broken top of the line VCR that has that bell and whistle.

Mark Zenier Washington State resident


--------------------------------------------------------

Actually, before going on a rampage through all the thrift shops (et
cetera) within a 179.52 mile radius, it's a really good idea to see if
your teevee has it built in.

Fer instance, on mine (Sony), go to the teevee menu, go to audio and
select "SAP".



Gray Shockley
--------------------------------------------------------
Looks Good/Lasts a Long Time