[net.ham-radio] squelch comments

rjr@mgweed.UUCP (Bob Roehrig) (07/16/85)

Most squelch circuits in FM receivers operate from detected noise, not AGC.
Most FM receivers do not even have AGC since limiting is necessary.
I do remember a few tube-type receivers that had some AGC applied to the
RF amplifier (like the Motorola "SENSICON").

Why try to eliminate the squelch tail anyway? It does serve as an audible
"over" signal. My only objection is to real long tails such as in a receiver
with a very loosely adjusted squelch.

Bob K9EUI

ron@brl-tgr.ARPA (Ron Natalie <ron>) (07/24/85)

> Why try to eliminate the squelch tail anyway? It does serve as an audible
> "over" signal. My only objection is to real long tails such as in a receiver
> with a very loosely adjusted squelch.
> 
Because it can be quite harsh, especially with repeaters like the old
07/67 in Baltimore that had no input receivers at the transmitter site.
When carrier was dropped, you would hear both the input receiver, the
link receiver, and your own radio's squelch tail.

-Ron