[TenTec] Re: Sound card audio problem

[Web Williams]

Something I have run into on -one- occasion, is that the outputof a soundcard had
voltage on it! 12VDC to be exact! The
speakers worked fine, I suppose they had DC blocking caps
in line (won't DC across a speaker voice coil burn the winding
in two?) somewhere inside the speaker system. Anyhow, when
my friend tried to mount a large 1/4 inch stereo output jack into
one of the fill plates on the back of the chassis, naturally he
connected audio ground to the jack and computer chassis. Turns
out that the speaker output on the sound card had it's ground
isolated from computer chassis ground for a reason (the DC
voltage). Anyhow, when power was applied to the computer,
the components of the sound card let out all their smoke, and
then ceased to work. (Everyone knows solid-state works based
on the amount of smoke held internally, right?) I'm not suggesting
that ALL sound cards run voltage to speaker-out, but this particular
one did. You might want to check before splicing into your audio
out lines, and perhaps consider the insertion of DC blocking caps
when fooling around with the speaker out terminals if you find DC
on the line. Generally speaking, I suppose the speaker jack being
plastic around the outside where it exits the sound card may be a
good hint that the jack shell is "hot".

73, -Web in Myrtle Beach, SC

P.S. I downloaded the PSK software, haven't installed it yet. Will
be on there someday real soon!

> Hi Guys/Gals,
>
> Thanks for all the help on the above problem.  It turns out that the right
> channel of my sound cards aux output is history.  Hooking up the left channel
> fixed the problem.  I also went the easy route and did everything through the
> fron MIC connector on the Corsair, and with the VOX it is a breeze.
>
> Hope to hear some of you on PSK!!
>
> 73, Jim  n0oct


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