Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.1 6/24/83; site burdvax.UUCP
Path: utzoo!linus!philabs!seismo!presby!burdvax!cad
From: cad@burdvax.UUCP
Newsgroups: net.audio
Subject: Re: FM compression
Message-ID: <1086@burdvax.UUCP>
Date: Fri, 16-Sep-83 23:25:38 EDT
Article-I.D.: burdvax.1086
Posted: Fri Sep 16 23:25:38 1983
Date-Received: Sun, 18-Sep-83 12:53:52 EDT
References: <435@houxf.UUCP>
Organization: SDC - a Burroughs Company, Paoli PA
Lines: 10

Yes most stations use compression to avoid overmodulation.
It is not required by the FCC.
This is not really compression, rather peak limiting.

Staions that use compression are trying to sound louder by 
increasing their average modulation.  The problem in trying to
"decode" the compression is that the amount of compression,
and the attack and decay times will vary from station to station
and from time to time as commercial stations strive to follow
local trends and studies on listener fatigue.