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Posting-Version: version B 2.10.1 6/24/83; site mgweed.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!ihnp4!mgnetp!mgweed!rjr
From: rjr@mgweed.UUCP (Bob Roehrig)
Newsgroups: net.ham-radio
Subject: PL, DTMF, etc  comments
Message-ID: <18736@mgweed.UUCP>
Date: Wed, 10-Jul-85 13:00:33 EDT
Article-I.D.: mgweed.18736
Posted: Wed Jul 10 13:00:33 1985
Date-Received: Fri, 12-Jul-85 00:56:20 EDT
Organization: AT&T Information Systems - Montgomery Illinois
Lines: 17


Yes, it is legal to use "PL" tones or DTMF tones for signalling as long
as that particular mode is authorized on the band you are using.

Remember one thing that MOST commercial stations using tone activated
receivers forget: DISABLE THE TONE CIRCUITRY BEFORE TRANSMITTING.
That is, except on the 440 MHz ham band, it is illegal to transmit on
a frequency before monitoring it. You can't do this unless you revert
to carrier squelch!

All "decent" repeaters that use subaudible tones have a 300 Hz (or so)
hi-pass filter in the audio path so the tone is not repeated. I really
hate to hear systems where people have their "PL" cranked up so high
that it garbles the voice. 

Bob K9EUI