Centipede speaker hum

[Neve...@aol.com]

I got Centipede up and running using Arcadeshop's Jamma adapter. Works
great. The only problem is that I have a speaker hum or buzz only when
the screen shows the brighter colors. Level one is fine, then two-
buzzzz. I tried changing wire polarity on the speaker and tried two
monitors. Perhaps the speaker assembly should be grounded? Any
advice?

Thanks.

, Bill

[Chris Bedwell]

Could be a noisy power supply ?.. or just noise ( of the RF type ) from the
monitor while it's working..

Have you tried a shielded speaker ?

Also, in the past - I've purchased clip on balun's and just put a couple of
loops in the speaker wire.. seem's to filter out the background mess..

I mainly had this problem with 25" and larger monitors.. weird, but the
small one's ( around 14" ) never used to have as many drama's until they got
really old..

- Chris.
www.myarcadegames.com
( Perth, Western Australia )

<Neve...@aol.com> wrote in message
news:1125099315....@o13g2000cwo.googlegroups.com...

[Neve...@aol.com]

Nope the noise comes from the speaker itself. When I get some time
I'll see if it's grounded. Maybe it's the speaker itself? When the
purple level comes up it's quite loud. . . Weird.

[Baraka]

Yo! Check your sound pot. Wiggle it around and see if the hum comes and
goes, if so, it's your sound pot Bill. Sometimes rotating a few times
back/forth will make it stop after it cleans itself. Otherwise, replace
the pot.

John

[dave...@gmail.com]

Make sure you have a sound pot in the connected in your cabinet. I had
this exact same problem and tried everything (large cap on the power
supply, grounded everything, swapped out power supplies) and nothing
worked. Then the other day it dawned on me that the jamma adapters
sound levels were very loud, so I grabbed a pot, wired it in and that
fixed the problem.

Now if I could just get rid of those other voices in my head...

--Dave

[bom...@gmail.com]

Dave,

Where did you wire the POT?

I have the same issue with mine.

-Tom

[Tom]

bom...@gmail.com wrote in news:1126665938.835351.263490
@z14g2000cwz.googlegroups.com:

Just wired in a 5k pot. Problem solved for me as well. Thank you for
posting your solution!!

-Tom