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From: rick@mips.UUCP
Newsgroups: net.micro.amiga
Subject: Re: Noise in left audio channel
Message-ID: <529@mips.UUCP>
Date: Mon, 23-Jun-86 20:52:40 EDT
Article-I.D.: mips.529
Posted: Mon Jun 23 20:52:40 1986
Date-Received: Wed, 25-Jun-86 06:18:16 EDT
References: <1290@well.UUCP> <1295@well.UUCP>
Organization: MIPS Computer Systems, Sunnyvale, CA
Lines: 26

I, too, experienced noise in one channel of my stereo when using a
modem.  I tried several things before finding out that the cables 
were indeed contributing to the problem.  Both serial and audio cables
were at fault.  The serial cable I use is a flat cable (25wires all laid out
in a flat fashion, NOT a shielded round cable) that had pins isolated at
the MODEM end.  This of course tends to make for a fairly good "antenna"
hanging out of the back of the amiga...  But more importantly, I had a
bad audio cable that had an open shield.  Add a fit of "neat-cable-fever"
where I taped all of the cables together one night while waiting for a
compile to finish, and you have a problem just waiting to jump and rear
it's ugly head.  (My machine exhibited the problem on the right channel..)
I probably compounded the effect by having my modem sitting on top of the
(unshielded) stereo cabinet as well.   During the debug phase of this "bug"
I took the case off of the Amiga and traced the circuitry back to the
drivers.  The circuit is terminated pretty well and I would not expect
your machine to be a cause of the problem.  First check for bad cables and
such.  Also be aware that taping the speaker cables to the telephone cord
(it's quite a ways to the phone jack sometimes) to make tings look
neater is not all that good of an idea either.  

--rick

-- 
--DISCLAIMER: All of the above is a personal opinion a result of imperfect--
--recall of facts (real or imagined) and in no way represents anyone else.--
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