Repairing a few pcbs today and thought I'd share a few tidbits on a particular board -

1. Completely Dead pcb -

• Checked 50 pin cables
  Checked rainbow cable (I use the edge connector)

Found bad connector on CPU pcb for rainbow cable
Fix - Replace connector

2. Pcb boots to random images of Mario's Hideout. No sound either. Cannot coin up.

• Checked sockets. 5B was not sitting properly

Fix - Replace socket and burned a new eprom. It ended up being just the socket, eprom tested fine in another pcb.

3. No digital sounds.

• Checked the output on pin6 on the DAC08, all is good
  

Fix - Pulled and socketed a new LM324 at 7K on the CPU board

Game now boots, credits and has sound. Although, missing the jump sound. Going to test the caps at C15-C27 and see whats causing the dead sound later this week.

Also, missing the blue and red, however, game plays fine. Going to check the transistors too...

This pcb was a mess too! Looked like someone tried to repair it already. OH boy!

Hope some of these items help you out. This was a multi problem pcb that will now live again.
More to come down the road.
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