No sound mv1f, narrowed down.

ovalfastlx

Kuroko's Training Dummy
Joined
Jul 30, 2017
Posts
78
I don't have any sound on my board. I have narrowed it down to being in the digital side of things, since I don't get sound on the sound test screen and just beeping on pin 4 of the Ym3016 with logic probe. I have two Ym2610, that I bought from China and they both give out no sound. So can it be something before the ym2610?

What else it can I check? The analog side, caps and whatnot, are OK.

Thanks guys.

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tobisham

n00b
Joined
May 18, 2017
Posts
6
To be sure, do you have oscilloscope activity on pin 31 of YM2610 (YM3016 serial data out) when doing the sound test? I understand you don't, so if it isn't the 2610 because you have already changed it, I would check all 2610 pins for activity against a working MVS
 

ovalfastlx

Kuroko's Training Dummy
Joined
Jul 30, 2017
Posts
78
To be sure, do you have oscilloscope activity on pin 31 of YM2610 (YM3016 serial data out) when doing the sound test? I understand you don't, so if it isn't the 2610 because you have already changed it, I would check all 2610 pins for activity against a working MVS

I have a Logic probe, I know the Clock pin 63 on 2610 sounded different on this board than my other board that works. I just stepped and bought a Logic Probe, now an oscilloscope would be cool, but can't justify buying one to fix one board. Thanks.
 

ovalfastlx

Kuroko's Training Dummy
Joined
Jul 30, 2017
Posts
78
After months FIXED!!!! Got Sound back.

After months of working on this board, I finally got sound back. I replaced the YM2610 and the z80 with a Z80A. After replacing the YM2610 and the z80, I still had no sound at the test menu, visually inspected traces and everything looked fine.

Testing for continuity all pins from YM2610 to Z80, I found Pin 56 on YM2610 to Pin 16 on the z80 did not have any continuity. This is the pin that had a resistor pack.
 
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