Centipede Sound Problem

<farrisgraphics DeleteThis @charter.net> wrote in message
news:1155998171.567173.170810@i42g2000cwa.googlegroups.com...
> I have a centepide with a sound problem. You can barely hear the game
> sounds with the volume turned all the way up, and a buzzing or
> interference tone coming from the speaker. Any suggestions on what it
> might be?

There are several things to try:

*) Remove the POKEY chip (the 40-pin chip that is NOT the 6502) and re-seat
it in its socket. This is the main sound generator for the game and there's
a chance that its audio output pin isn't making good contact with its
socket.

*) Measure all of the voltages on the motherboard. There are several test
points for +5 volts, +12 volts, and -5 volts. If one of these is missing or
is of the wrong value, the audio mixing circuitry won't work properly.

*) It could be the actual audio amplifier chip on the Audio/Regulator board.
One way to find out for sure is to take a pocket audio amplifier and connect
it to the motherboard's AUD1 or AUD2 test point. If you're still not
getting good audio, then you've confined the problem to the motherboard.
(You can use your powered speakers from your PC by using alligator clips.)
 >> Stay informed about: Centipede Sound Problem 

Thanks for the info guys. Much more info than I had before. I'll let
you know the outcome.

Thanks, Jim


Pat D. wrote:
> That 3rd step is a great idea. Have to make a set and throw it in my
> repair bag.
>
> Pat D.
>
> Matt J. McCullar wrote:
> > <farrisgraphics DeleteThis @charter.net> wrote in message
> > news:1155998171.567173.170810@i42g2000cwa.googlegroups.com...
> >> I have a centepide with a sound problem. You can barely hear the game
> >> sounds with the volume turned all the way up, and a buzzing or
> >> interference tone coming from the speaker. Any suggestions on what it
> >> might be?
> >
> > There are several things to try:
> >
> > *) Remove the POKEY chip (the 40-pin chip that is NOT the 6502) and re-seat
> > it in its socket. This is the main sound generator for the game and there's
> > a chance that its audio output pin isn't making good contact with its
> > socket.
> >
> > *) Measure all of the voltages on the motherboard. There are several test
> > points for +5 volts, +12 volts, and -5 volts. If one of these is missing or
> > is of the wrong value, the audio mixing circuitry won't work properly.
> >
> > *) It could be the actual audio amplifier chip on the Audio/Regulator board.
> > One way to find out for sure is to take a pocket audio amplifier and connect
> > it to the motherboard's AUD1 or AUD2 test point. If you're still not
> > getting good audio, then you've confined the problem to the motherboard.
> > (You can use your powered speakers from your PC by using alligator clips.)
> >
> >
> >
> >
 >> Stay informed about: Centipede Sound Problem 

That 3rd step is a great idea. Have to make a set and throw it in my
repair bag.

Pat D.

Matt J. McCullar wrote:
> <farrisgraphics.DeleteThis@charter.net> wrote in message
> news:1155998171.567173.170810@i42g2000cwa.googlegroups.com...
>> I have a centepide with a sound problem. You can barely hear the game
>> sounds with the volume turned all the way up, and a buzzing or
>> interference tone coming from the speaker. Any suggestions on what it
>> might be?
>
> There are several things to try:
>
> *) Remove the POKEY chip (the 40-pin chip that is NOT the 6502) and re-seat
> it in its socket. This is the main sound generator for the game and there's
> a chance that its audio output pin isn't making good contact with its
> socket.
>
> *) Measure all of the voltages on the motherboard. There are several test
> points for +5 volts, +12 volts, and -5 volts. If one of these is missing or
> is of the wrong value, the audio mixing circuitry won't work properly.
>
> *) It could be the actual audio amplifier chip on the Audio/Regulator board.
> One way to find out for sure is to take a pocket audio amplifier and connect
> it to the motherboard's AUD1 or AUD2 test point. If you're still not
> getting good audio, then you've confined the problem to the motherboard.
> (You can use your powered speakers from your PC by using alligator clips.)
>
>
>
>
 >> Stay informed about: Centipede Sound Problem