Ron wrote:

>FM repeaters, for example, sometimes use the "beep" to signal when the
>repeater drops the carrier, since that happens after a delay following
>the last transmission.

Most repeater systems which generate that "beep" do so to indicate that the 
time-out timer (TOT) has just reset, well before the output carrier is dropped. 
 The TOT limits how long an uninterupted input signal will be repeated before 
the repeater's output transmission is stopped.  The TOT resets after the 
*input* carrier has dropped, the beep is sent, and the repeater's output 
carrier stays on for several seconds longer.  After the TOT reset beep has been 
heard, the next party may begin transmission with a re-initialized TOT.  The 
repeater output carrier need *never* drop through a whole QSO.

On repeater systems without such a TOT reset signal, only the drop out of the 
repeater output signal can be used to positively indicate TOT reset.  In 
repeater applications such beeps are useful, although the volume and tone 
frequency seem most often to have been chosen to be as irritating as possible.

Mike / KK5F
_______________________________________________
Elecraft mailing list
Post to: Elecraft@mailman.qth.net
You must be a subscriber to post to the list.
Subscriber Info (Addr. Change, sub, unsub etc.):
 http://mailman.qth.net/mailman/listinfo/elecraft    

Help: http://mailman.qth.net/subscribers.htm
Elecraft web page: http://www.elecraft.com

Reply via email to