Modem tones over television or radio

From: CLASSICCMP_at_trailing-edge.com <(CLASSICCMP_at_trailing-edge.com)>
Date: Thu Dec 10 10:11:59 1998

>Somewhat apropos the recent thread about sending mains power
>through modems, can anyone tell me if it's legal or illegal
>here in the States to send data in the audio of television or
>radio?

Yes - and it's commonly done. The new Emergency Broadcast
System replacement transmits 1200 bps (I believe Bell 212A
modulation) bursts over TV and radio audio. And many different
digital services are encoded in the video blanking interval of
TV signals - closed captioning, timestamps, and program
information, among others.

> Certainly there would be bandwidth and therefore speed
>limitations, but does the FCC allow this?

It's a requirement of the new EBS replacement!

-- 
 Tim Shoppa                        Email: shoppa_at_trailing-edge.com
 Trailing Edge Technology          WWW:   http://www.trailing-edge.com/
 7328 Bradley Blvd		   Voice: 301-767-5917
 Bethesda, MD, USA 20817           Fax:   301-767-5927
Received on Thu Dec 10 1998 - 10:11:59 GMT

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