Article View: sci.electronics
Article #8314Audio from a VGA card
From: Ross Ackland
Date: Mon, 12 Nov 1990 23:51
Date: Mon, 12 Nov 1990 23:51
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1786 bytes
The other day, an idea struck me from the twilight zone. It seemed stupid
at first but the more I thought about it the more it seemed feasible.
The video DAC's on a VGA card (IBM-PC) are good for quite a few MHz,
so would it be possible to generate audio from them in the form of music
or speech?
I guess a low pass filter would help. You would cut one or two lines going
to the monitor and stick them into an amplifier. Hey, the video signal should
be well above the audio range, what about video and audio at the same time
(that would be impressive!).
Or, we could even modulate the audio (using the palette registers) and build
an AM transmitter!!!! What happens to the signal during vertical and
horizontal retrace? I don't know enough about programming VGA's at the
register level (I wish I did).
I'm beginining to get out of control on this one and my days of undergraduate
Elec Eng and signal theory are long gone.
Don't flame me for this, if its beyond the ridiculous then let me die a
natural death, if you think its feasible then lets hear your ideas...
Ross Ackland
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Path: arc1-ca.pugleaf.net!utzoo!attcan!uunet!munnari.oz.au!csc.anu.oz.au!csis!rackland From: rackland@csis.dit.csiro.au (Ross Ackland) Newsgroups: sci.electronics Subject: Audio from a VGA card Message-ID: <1990Nov12.235118.29947@csis.dit.csiro.au> Date: 12 Nov 90 23:51:18 GMT Organization: CSIRO Div of Inf Tech Lines: 33