Update
I've been doing some working on my boards - and yesterday I finished the CPU board
Repairs / mods that I have done include:
- Replaced U11, U12, U13, U14, and U15 - and socketed all the chips
- Fixed some dodgey traces, and removed the wire jumpers that had been in place on the rear of the board
- Replaced the U9 - 84 pin socket, as the original one had a crack in one corner
- Replaced U6 with a new LH6 ROM - from 'That Pinball Place' - thanks johnwartjr
- Replaced the 0 ohm diode at W18 - because I'm too lazy to learn German
- Made up a remote battery holder
After all that I hooked up an old PC power supply to J210 - and............ nothing
All three LED's stayed on, no flashes, no nothing - Bugger!!!
I pushed IC's, pulled out the ROM, ASIC, and checked all my soldering - but it didn't want to play.
Today I sent Beaky a message for some assistance, and as the good bloke that he is, he came back with a few tips to follow. Before I ventured down the path of more IC replacements, I though I'd have another go at booting the board, but this time with a different power supply as the first one I had tried was only putting out 4.95 volts instead of 5.00 volts.
Not feeling too confident, I hooked up the next power supply which was putting out 5.35 volts, and voila! - the board booted, and now the LED's were all doing their thing.
I would like to thank Beaky for taking the time to answer my questions, and hope that as I go on he'll be happy to answer more
Here are a couple of before and after photos of the CPU - now to finish off the rest!