Gunforce PCB: resistor value needed from sound section...

ifkz

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Gunforce PCB: resistor value needed from sound section...

I got another one of my arcade favorites in the mail yesterday only to find an undisclosed audio issue: a burned up resistor in the audio section. I am sure the seller and I will work something out for the trouble.

In the meantime, this burned up resistor causes the sound to be very quiet and I noticed it cuts out entirely in some instances. I need either the color bands for the resistor or the value. The resistor is at location R201

Here is a pretty clear picture:
HPIM1469-1.jpg
 
That resistor is : Brown - Black - Red - Gold or 1k ohm with a +/- 5% tolerance.

I'm glad I get a chance to return the favor from your help with the Zero Team boards.
 

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You rock! It looks like a quarter watt to me, hopefully I can scavenge one from a parts board. Maybe I'll upgrade it to a half watt, just in case.
 
Okay, I got it installed and so far, so good. I upgraded it to a half watt. Sound levels are normal, the static is gone and....

Edit: Sound cut out. Shoot...
 
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Well, it has been happily playing with sound in the demo mode for about 25 minutes now (update below).

I pulled it apart and reseated both boards and all socketed chips.
I cleaned all dead spider bodies and webs from the sockets and solder side of the boards.
I dumped as many EPROMS as I could, except the NECs because my Wiliem programmer can't read 'em. They verified correctly.
One chip had taken a hit and had all pins bent at angles. They were straightened out and the chip appears to be a real trooper and is okay.
The new resistor I put in hasn't caught on fire (yet). All good things.

The YM1251 chip that generates the different sounds runs pretty hot, that may be the culprit. If the sound dies again I'll fit a socket and new chip to the board (provided I have one in my scrap pile)

Whew!

EDIT: Looks like it is socket time and time for me to hunt through my parts boards. It ran fine in demo mode for 35 minutes but when I started a game the sound system crashed again. This board hates me...
 
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Update. Instead of replacing the YM chip, I decided to start with simply cleaning the socketed chips with an emery board to removed oxidation and other contaminants from over the years. Four complete play throughs have been perfect and I think the YM chip is running cooler. Dare I say...fixed?
 
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