Re: IIgs Sound Question

[dalloff@freenet.columbus.oh.us (Dave Althoff)]

Paul Grammens (pgrammen@sonic.net) wrote:
: I have a IIgs motherbd that causes a continual "frying" noise from the
: speaker. Otherwise the sound seems normal. I noticed a transistor and
: maybe a few other parts added in the area of the sound circuitry. Looks
: like it was a modification done at the factory. Anyone know what the
: purpose of the xtra parts is, and if it might have any relation to the
: noise? I have another board with a video problem (colors are way off)
: that doesn't make this noise, and doesn't have the modification.
: -Paul

A ROM 01 machine, right?  I have one on my desk at work that does the same
thing.  I did notice that the noise got steadily more frequent until it
sounded like there was a major thunderstorm going on inside the case; then
before long the power supply died.  I replaced the power supply (with
another GS supply) and it still occasionally makes the noise, but not as
loud and not as frequently.

I'm guessing that the power supply - noise connection is just a
coincidence...although my GS at home also has the board modification you
describe (as does the one at work), and does NOT make the static
noise...and it has an AE high-output power supply (an old Vulcan-20).  I'm
still not convinced that there is a relationship between the power supply
and the noise, but there is some evidence that such a relationship may exist.

--Dave Althoff, ][.
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