Punchout Audio Problem

postmortem01

Permanently Banned. Verified second account used f
Joined
Jan 27, 2011
Messages
270
Reaction score
0
Location
Newhall, California
I just picked up a punchout project cabinet. Amongst other things, I'm having a couple audio issues. The music channel sound sounds like the speaker is blown but it's not. I've recapped the audio amplifier board but still sounds distorted. The voice channel is not even working at all. Any ideas?

Could it be a board issue?
 
You are aware there are 2 audio boards on PunchOut? One on each Monitor. You have rebuilt both?
On the main game PCB there are two sound chips. The first is at 4H, a 74LS377.
The other is the 2A03. This chip controls most everything except the announcer's speech. Mike's Arcade -has the 2A03 here.....
http://www.mikesarcade.com/cgi-bin/store.pl?sku=RP2A03
 
You are aware there are 2 audio boards on PunchOut? One on each Monitor. You have rebuilt both?
On the main game PCB there are two sound chips. The first is at 4H, a 74LS377.
The other is the 2A03. This chip controls most everything except the announcer's speech. Mike's Arcade -has the 2A03 here.....
http://www.mikesarcade.com/cgi-bin/store.pl?sku=RP2A03


I just had to chime in... I am blown away at the amount of information all the users on this site have!!
 
Hello. Thanks very much for the replies. I am aware that there are two audio boards. I've recapped them both. I found something strange...

C378 was missing on both. There was no solder on that point on either board. The cap kits come with that capacitor. I tried the boards without the capacitors and then with the capacitors. Same result in both instances.

I'm going to pull a working audio board from popeye or Mario Bros and tes it in the machine on both audio channels tonight just to make sure that the pcb is the problem.

I'm getting audio, it's just distorted. Does this sound chip related?
 
I'm getting audio, it's just distorted. Does this sound chip related?

Possibly? I can't remember the symptoms mine had when my issue. I don't recall any distortion. My 2A03 was bad, I was missing the attract sounds that play when you are putting in your name, the sound when you knock your opponent down, a few other random sounds....As I recall there were some sounds that you could sometimes here that sounds very faint, or full of static.....I had the announcer voice....

C378 was missing on both. There was no solder on that point on either board
Visually compare to your know good board on your MB.....
Then try each of your audio boards in your MB and report the results.
 
Possibly? I can't remember the symptoms mine had when my issue. I don't recall any distortion. My 2A03 was bad, I was missing the attract sounds that play when you are putting in your name, the sound when you knock your opponent down, a few other random sounds....As I recall there were some sounds that you could sometimes here that sounds very faint, or full of static.....I had the announcer voice....

Visually compare to your know good board on your MB.....
Then try each of your audio boards in your MB and report the results.

Nice. Now I know how to fix mine. Same exact problem since I've had it. I lived with it because it doesn't affect gameplay too much.
 
Okay. finally figured out what was wrong with the audio amplifiers. Both amplifiers had bad resistors at R383. Problem solved with new resistors and cap kits!

Thanks guys.
 
Are these the same boards in Donkey Kong Jr? I did a cap kit on a audio board and it still sounded bad afterwords.
 
Back
Top Bottom