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From: tk@rpiacm.UUCP
Newsgroups: comp.misc
Subject: Re: More 1130/1403 stuff
Message-ID: <151@rpiacm.UUCP>
Date: Wed, 25-Feb-87 16:18:42 EST
Article-I.D.: rpiacm.151
Posted: Wed Feb 25 16:18:42 1987
Date-Received: Sun, 1-Mar-87 14:37:25 EST
References: <2319@sunybcs.UUCP> <1596@kitty.UUCP> <984@osiris.UUCP> <290@dasys1.UUCP>
Lines: 21
Keywords: early computers, trivia, humor
Summary: TRS-80 Model I Sound effects

In article <290@dasys1.UUCP>, rsweeney@dasys1.UUCP (Robert Sweeney) writes:
> Before the FCC AM interference regulations were passed, you used to
> be able to do this sort of thing with just about any machine.
> I remember playing early TRS-80 games, like "Invasion Force",
> and using a large AM radio placed near the machine to produce
> appropriate sound effects.  In fact, TRS-80 programmers got so good
> at producing the correct sound-creating loops that some of the later
> games actually had VOICE effects!

Yes - I still have my TRS-80 Model I and remember the sound effects that were
produced in that manner. However, it wasn't QUITE as impressive as it might
seem. What was really going on was that the game sent out the sound in the form
of square wave pulses to the cassette port (which is why you could get clearer
sound by hooking up a speaker to the AUX jack). It just happened to be true that
the RFI from the machine was bad enough to also make those sounds audible on an
unused AM frequency...
-- 
Ron Frederick
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