[aprssig] OT: FRS radios and PTT

Steve Noskowicz noskosteve at yahoo.com
Mon Mar 14 15:10:01 EDT 2011

-- Stephen Smith wrote:
> Motorola tone-remote control for land-mobile radio base stations:
> Low level tone sent over the TX voice audio channel that is then
> notched out at the remote radio site.    One could even do the 
> loud initial beep for positive keying and then drop the tone 
> 20 dB for hold during voice.

This I like too, but the VOX has to be agreeable to the low level.  Having a comm analyzer would do the trick.

> I find VOX on FM really obnoxious 

So true.  So true.  One of the locals was laid up and had to use it so you just put up with it, but normally it stinks.

Once you truly understand how things work you can do some fun things.  There are things like this that come in handy for repeater control if you don't have the control codes handy and need some jammer 'intervention'...

73, Steve, K9DCI


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