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Moo-Mesa Konami Sound Chip problem

Posted: March 10th, 2017, 1:08 pm
by Moonwalker
Hi,

I have a Moo Mesa PCB with the infamous Konami sound chip on it. Somebody tried to repair it by replacing the caps on the chip itself (quite sloppy job) but it did not work. I also replaced the Yamaha sound chip - no success.

The board starts with a test and tells "SOUND SYSTEM BAD", resseting and testing again in an infinite loop.

can anybody help?

Thanks in advance!

Re: Moo-Mesa Konami Sound Chip problem

Posted: March 10th, 2017, 5:43 pm
by zak
HAve you tried IronGiant for repair? He's done a lot of these. They're not easy to repair

Re: Moo-Mesa Konami Sound Chip problem

Posted: March 10th, 2017, 6:29 pm
by thechop
Yeah he's done a couple of xexex pcbs for me in the past, top job.
Trouble is if someone has already had a go at it it may not be repairable.

Re: Moo-Mesa Konami Sound Chip problem

Posted: March 10th, 2017, 8:22 pm
by Ace`
I don't know if Moo Mesa is any thing like Bucky but I had the same issue with a Bucky 'o hare board, I reflowed the konami custom in the sound area to fix it.

Re: Moo-Mesa Konami Sound Chip problem

Posted: March 13th, 2017, 11:14 am
by Moonwalker
zak wrote:HAve you tried IronGiant for repair? He's done a lot of these. They're not easy to repair
No, thanks! I will try to contact him. I can find him here, right?
EDIT: I can´t find him here... Can anybody tell me how to contact him please?
Ace` wrote:I don't know if Moo Mesa is any thing like Bucky but I had the same issue with a Bucky 'o hare board, I reflowed the konami custom in the sound area to fix it.
Most of the Konami boards are very similar and the sound chip is the same. Will try that, but it looks like it was done before when changing the caps.

Re: Moo-Mesa Konami Sound Chip problem

Posted: March 13th, 2017, 12:55 pm
by frsj8112
have you checked the RAM for the audio section?

Re: Moo-Mesa Konami Sound Chip problem

Posted: March 13th, 2017, 2:17 pm
by zak
Moonwalker wrote:
zak wrote:HAve you tried IronGiant for repair? He's done a lot of these. They're not easy to repair
No, thanks! I will try to contact him. I can find him here, right?
EDIT: I can´t find him here... Can anybody tell me how to contact him please?
Ace` wrote:I don't know if Moo Mesa is any thing like Bucky but I had the same issue with a Bucky 'o hare board, I reflowed the konami custom in the sound area to fix it.
Most of the Konami boards are very similar and the sound chip is the same. Will try that, but it looks like it was done before when changing the caps.
Sorry, his name is VectorGlow on this forum. Here is his profile page:

http://forum.arcadeotaku.com/memberlist ... file&u=517

Re: Moo-Mesa Konami Sound Chip problem

Posted: March 13th, 2017, 2:54 pm
by VectorGlow
IronGiant here (known as Vectorglow on this forum) - thanks for the recommendations folks.

Re the Moo Mesa - those sound hybrid chips can also suffer from corrosion if the older electrolytic caps were leaking before being replaced - on the underside of the hybrid is another surface mounted chip or two. I don't recall if the error that you are seeing could be caused by one of those chips having a problem - however I do know that just the electrolytics failing won't cause the sound system error.

It's quite likely that another chip in the sound circuit has failed.

As for repairing the board, happy to take a look at it if you're not in a hurry - recent family problems have caused me to cease work for a while due to sorting out all kinds of things. However, I hope to get back to work in a few weeks. @Moonwalker - are you in a hurry for the repair?

Feel free to PM me here.

Re: Moo-Mesa Konami Sound Chip problem

Posted: March 13th, 2017, 4:27 pm
by Moonwalker
Great - PM incoming!

Re: Moo-Mesa Konami Sound Chip problem

Posted: April 5th, 2017, 3:00 pm
by caius
VectorGlow wrote:IronGiant here (known as Vectorglow on this forum) - thanks for the recommendations folks.

Re the Moo Mesa - those sound hybrid chips can also suffer from corrosion if the older electrolytic caps were leaking before being replaced - on the underside of the hybrid is another surface mounted chip or two. I don't recall if the error that you are seeing could be caused by one of those chips having a problem - however I do know that just the electrolytics failing won't cause the sound system error.
How can electrolytic capacitors and DAC (parts of the analog circuit) cause an issue that is related to digital circuit??? :)
The "SOUND SYSTEM BAD" error is clearly related to digital circuit, I suspect some broken traces from '054321' ASIC on the module to its legs.Bucky o' Hare can show this error if the YM2151 is bad.

Re: Moo-Mesa Konami Sound Chip problem

Posted: April 5th, 2017, 3:06 pm
by frsj8112
If I would send off a PCB for repair, I would send it to caius.
Just look at his repairlogs on www.jammarcade.net, top work and good understanding of arcade hardware architecture.

Re: Moo-Mesa Konami Sound Chip problem

Posted: April 22nd, 2017, 7:58 am
by vasilas432
+1 to caius
He has replaced those caps on Konami chip in 4 Konami boards of mine

Re: Moo-Mesa Konami Sound Chip problem

Posted: May 3rd, 2017, 10:47 pm
by caius
I received this PCB today and I was able to repair it.You can read log here:

http://www.jammarcade.net/wild-west-c-o ... air-log-3/

Thanks to Moonwalker for sending me the PCB and to VectorGlow for the report of his previous work

Re: Moo-Mesa Konami Sound Chip problem

Posted: May 4th, 2017, 12:56 am
by Asure
I need to send you a box of pcb's some day, you're a wizard!

Re: Moo-Mesa Konami Sound Chip problem

Posted: May 4th, 2017, 1:04 am
by caius
Thanks but I'm not a wizard, often people overstimate me and my skills.I only work hard and never give up, thats the key.

Re: Moo-Mesa Konami Sound Chip problem

Posted: May 4th, 2017, 4:20 pm
by zak
caius wrote:Thanks but I'm not a wizard, often people overstimate me and my skills.I only work hard and never give up, thats the key.
Says the wizards ;)

Re: Moo-Mesa Konami Sound Chip problem

Posted: May 16th, 2017, 4:02 pm
by Moonwalker
Thanks VectorGlow and Caius for the great work!
I have a working Moo Mesa and Double Dragon 3 board again :)

Re: Moo-Mesa Konami Sound Chip problem

Posted: May 16th, 2017, 7:20 pm
by caius
Thanks to you and enjoy your (repaired) boards!

Re: Moo-Mesa Konami Sound Chip problem

Posted: May 27th, 2017, 2:51 am
by zumbito
caius wrote:I received this PCB today and I was able to repair it.You can read log here:

http://www.jammarcade.net/wild-west-c-o ... air-log-3/

Thanks to Moonwalker for sending me the PCB and to VectorGlow for the report of his previous work
Amazing, I have the same problem with a Bucky O'hare, no sound. Someone already recapped it, but the chip looks really corroded, not sure what to do with it.

Re: Moo-Mesa Konami Sound Chip problem

Posted: June 4th, 2017, 1:45 am
by caius
Try to replace the '054896A" module or chance the 4558 OP-AMP on its underneath.