Donkey Kong Jr image sparkles ?

RPO_Z06

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I know I've read somewhere about this but I can't seem to find it, I have a DK Jr video board with slight image sparkles that I can't seem to figure out.

It goes away after the board warms up, I can adjust the vertical pot up and down a few times to make it stop, I replaced the pots on the board even though they tested good I had a pair and thought it was worth a shot but it had no effect.

Anyone have an idea ?
 
Are the ECL's are the three with the heat sinks on them in locations 2H, 2E and 1E ? Would there be any way to test them ? 1E is missing its heat sink.
 
It goes away after the board warms up,

The article you were looking for:

Problem: Sparklies or Graphic glitches.
This is a pretty common problem on DKjr and DK boards, but this is the first time I've found a cure.
This particular board was fine until I let it run about 1/2 hour. I had upgraded it to DDK and when testing it as a Jr board saw no problems, but didn't' let it run too long before I upgraded it.
After the upgrade, I let it sit and burn-in while I went to eat dinner. When I came back, the top or the screen above Polly screaming help in DK was filled with glitches! I booted over to DKJr and the key on the top exhibited the same problem with sparkly glitches. So, I grabbed a can of freeze spray. All the ECLs were really hot to the touch, so I hit them one at a time, then watched the screen. The faulty chips was a MC10124 at 4H, this chip is a quad TTL->MECL translator. The MC10125 is it's counter-part and goes from MECL->TTL.
After letting it run another 1/2 hour or so, in DK mode I noticed just a few sparklies at the top, under the high score. So I shot the MC10125 at 4F with freeze spray and watched for more sparklies. As long as I shot the chip every couple of seconds, the sparklies didn't show up. If I waited a few minutes, they would again appear. Changing both chips solved the sparkly problem with this board.
Solution: 2 bad ECL translators, an MC10124 at 4H and the MC10125 at 4F.
 
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