DK 4 board No Jump sound

Talon2000

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Got a 4 board stack, TKG3 that has no Mario Jump sound.

Complete re-cap of the Sound board no help.
Replaced all the 10uf caps on the CPU board No help.

Radar Scope schematics only list sounds as Sound0-Sound7 no names given.

I'm almost certain the sound is there, it's very very faint. Thinking it might be a cap, but as of yet I've been unable to nail it down.

Anyone know which caps are in that sound circuit?

Thanks
 
Went ahead and replaced all electrolyics on all boards, no change.

Pulled and checked all the transistors on the sound board. Still nothing.
 
Make sure when you replace the 555/556/558 timer chips that you use the same type!

Radio Shack sells the pesky 555 timer chip as a CMOS type and if you use that you'll get a slightly higher pitch to the sounds on a Galaxian. Same thing if you use it as a replacement in a vector monitor - a slightly higher frequency.

RJ
 
Make sure when you replace the 555/556/558 timer chips that you use the same type!

Radio Shack sells the pesky 555 timer chip as a CMOS type and if you use that you'll get a slightly higher pitch to the sounds on a Galaxian. Same thing if you use it as a replacement in a vector monitor - a slightly higher frequency.

Interesting. It's knowledge nuggets like this that keep me coming back here...
 
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