New Donkey Kong Jr - Few issues

I am happy to report that after switching out the B+, the machine is now working again! I did notice, when I took the board out of the monitor again, that there was a black wire with a "U-Connector" (Ground, I believe) that I somehow did not reattach the last time I was I was in there. This certainly could have caused me a problem!

Regardless, for now the machine appears to be working. Next on the list is to figure out the sound!

Next remind us on whats up with the audio is it pcb or monitor related? A way I've heard you can test is try finding the ground and signal getting little alligator clips on the pcb and hook them corresponding to some headphones see if you can hear anything. If you hear something its monitor issues if you hear nothing pcb. I've heard of people doing that never myself though.
 
Next remind us on whats up with the audio is it pcb or monitor related? A way I've heard you can test is try finding the ground and signal getting little alligator clips on the pcb and hook them corresponding to some headphones see if you can hear anything. If you hear something its monitor issues if you hear nothing pcb. I've heard of people doing that never myself though.

Well - P10 isn't putting out 5V. So I need to figure out that back to the power supply (Which I am not sure how to test on a nintendo machine) and try and find the problem there.
 
Hmmm. Did not know this. Can you clarify how I'd hook it up to a audio amp?

So basically there's a negative and positive signal. That sound gets amplified and sent to a speaker. if you got a little audio amp you can test the pcb and see if thats the issue.
 
Here we go!

Here is a picture of the power supply with the wires coming off of it.

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Next, here is a picture of the P10 which is responsible for the sound. This originally had 0V. I replaced C13 with the yellow cap below it, and now it produces around 1 volt.

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Here is a close up of the replaced cap.

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The wire from P10 run to this board.

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Here is a shot of the whole PCB.

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hold up on this picture you replaced a cap with a non polar one. I dont think that pcb has any of those. You need to put a polarized one there I think.
 
hold up on this picture you replaced a cap with a non polar one. I dont think that pcb has any of those. You need to put a polarized one there I think.

Ian Kellogg felt it would be okay - but I am not sure. I know the speaker hums when its on - and if you turn the volumn up, the hum gets louder. I'll attempt to find a new cap.
 
Hmm then the issue is deffo on the pcb. Try replacing the cap and just on a whim here see if the sound z80 getting super hot or not hot at all after running for like 20 minutes. If its super hot its shorted somewhere and not making any sound if its cold its dead and not making any sound.
 
HOLY CRAP! Its fixed!

So this is a funny story. The wire to the speaker was disconnected, which I knew - but when I turned on the game, and held the wire to the speaker....no sound. So due to this, I assumed (you know what happens when you assume).....

So today, I properly connected the wire to the speaker just so that it would not be hanging around.

I - then - decided to start a game - and much to my surprise, was greeted with SOUND!!!

Apparently - I guess (??) that there is no attract sounds on this game? When I start a game, it makes plenty of sounds and plays its music while I am going.

Regardless!!!

3 issues down, and 1 to go! The pesky coin mechs!!
 
That's a good and easy resolution. You can turn attract mode sounds on via a dip switch, but default is off.
HOLY CRAP! Its fixed!

So this is a funny story. The wire to the speaker was disconnected, which I knew - but when I turned on the game, and held the wire to the speaker....no sound. So due to this, I assumed (you know what happens when you assume).....

So today, I properly connected the wire to the speaker just so that it would not be hanging around.

I - then - decided to start a game - and much to my surprise, was greeted with SOUND!!!

Apparently - I guess (??) that there is no attract sounds on this game? When I start a game, it makes plenty of sounds and plays its music while I am going.

Regardless!!!

3 issues down, and 1 to go! The pesky coin mechs!!
 
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