Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ncar!stout!cook
From: cook@stout.ucar.edu (Forrest Cook)
Newsgroups: sci.electronics
Subject: Re: IBM-PC Volume Control
Message-ID: <3270@ncar.ucar.edu>
Date: 19 May 89 19:59:22 GMT
References: <2373@Portia.Stanford.EDU>
Sender: news@ncar.ucar.edu
Reply-To: cook@stout.UCAR.EDU (Forrest Cook)
Organization: Field Observing Facility, NCAR, Boulder, CO
Lines: 24

In article <2373@Portia.Stanford.EDU> jimb@Portia.Stanford.EDU (Jim Bjorksten) writes:
>Is there a way to adjust the volume on my IBM-PC??
>-Jim

Yes, I added a volume control to a PC here at work.  Here is the schematic:

PC SPK: ------------------|                  /|
                          /               --/ |
                   100    \ <-------------|   | SPKR
                   OHM    /        |------|   |
                   POT    \        |      --\ |
                          /        |         \|
PC GND:	------------------|--------|

An audio taper potentiometer would be "proper" here, but linear pots are
easier to find at 100 ohms and work fine.

Too bad IBM didn't put a DAC in front of the speaker, square waves are
kind of limiting.

 ^   ^  Forrest Cook - Beware of programmers who carry screwdrivers - LB
/|\ /|\ cook@stout.ucar.edu (The preceeding was all my OPINION)
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