Centipede sound issue..

Muerto

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suddenly the other day when i was playing a game of centipede, the sound died, today i had some time to take a closer look....

when i turned it on, and pressed 1 player, there vas a very very faint sound wich died 2 sec later but if i turn the volume up to max, i can hear the sound very very (VERY) faint..

is there sonthing wrong with the AUX/Audio board or the "knob" wich controls the volume level?
 
Your "knob" is probably OK. Check voltages on the Audio/Regulator board. If all voltages are present....I'd start with one of the TDA2002 on the A/R board...or the LM324 on the motherboard.

Edward
 
.... wich is the TDA2002?
tda2002.jpg
 
ok, found them! (im pretty green at this!)

Im not sure what the voltage should be, but when i try to messure the voltage on Q5 and Q7, the speaker humms like crazy...
do you know what the voltages should be?

power.jpg


power2.jpg
 
Just use the test points on the A/R board.....The ones for the audio are 12VDC, -5VDC, and the 10.3VDC.

Edward
 
ok, there´s somthing serious wrong here!!!

12VDC reads 12
-5VDC reads -2
10.3VDC reads 13

where can i ajust that?

That's probably the problem. The -5VDC regulator is shot. 13VDC on the 10.3VDC rail is fine. That line is unregulated....and almost always reads high.

Replace Q9 (LM7905) on the A/R board and report back.

Edward
 
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