Board # 1		Status upon arrival:  DOA.  Repairs:  Board was  filthy and missing many of the socketed chips - Z-80 CPU, all row 6 ROM as well as the 5E and 5F ROM.  None of the RAM in row 4  had any signs of life.  All row 4 RAM sockets replaced and it turned out all the original RAM was just fine.  R43 resistor was broken in half and replaced.  Edge connector pads repaired.  Voltage was a steady 4.94vdc and the crystal spot on.  All new 2532 ROM’s were burned  and installed. A new Z-80 CPU was put back in place.  No real video (occasional garbled out of sync image) but sounds could be heard of a repeating credit/coin drop.  The counter at 2S was found to have faulty outputs – socketed and replaced.  This brough back a solid video game screen.  Game would boot but only the attract screen was correct.  Start of a game immediately went to a completed screen and then to  the intermission (strange!).  The credits still counted rapid fire up until 99 credits.  The credit/coin control circuit checked fine at 8E and 8H along with all the associated resistors and capacitors.  However, the feed signal from 7J pin 11 was stuck high causing the non-stop credit addition issue.  Comparator confirmed the issue.  7J socketed and replaced.  Board now works!
Board # 2		Status upon arrival:  DOA.D Repairs: Board was  filthy and missing  many of the socketed chips - Z-80 CPU and all the  row 6 ROM. Board marked many years ago ‘Needs Board Work’.  Edge connector pads repaired.  Voltage steady 4.96vdc and crystal spot on.  The socket at 284 was well past its usable life – replaced.  All new 2532 ROM’s burned and a new Z-80 put back in place.  FPGA confirmed all RAM/ROM working.  Socket at 3R was damaged from an impact breaking off the power pin – replaced.  Faulty sockets replaced at 4A and 7F.  Board still dead (no video) with no output at 7F.  All row 2 RAM pin 7 stuck high.   VBLANK signal missing and confirmed with comparator 2P was at fault.  Replaced and video image finally on the screen but out of sync.  Corroded pin 9 found at 2R.  Socketed and replaced – now have a solid image on the screen. Board now works!
Board # 3		Status upon arrival:  DOA. D Repairs:  Board had been previously designated as a parts board (Oh boy!).  Many parts were salvaged from this board from over the years.  Parts missing: Q6 transistor missing on the heat sink, Z80, all ROM, 4ohm resistor at R5, 7F, 4A, R48, RAM 2A, RAM 2B, 1R1 voltage regulator, etc.  Used a TIP31 for the 5vdc circuit, re-capped the board (many caps out of tolerance), replaced all missing parts.  All new 2532 ROM’s burned.  Edge connector pads repaired.  Board still dead with minimal signs of life.  5vdc still not looking well.  Diodes at D7/D8 were showing significant signs of leakage on my B&K 520B.  Replaced with IN5404.  Voltage still not back.  Turns out the Zener diode at D9 was shorted.  Replaced – solid 4.98vdc finally back.  Almost no activity on the row 6 ROM and the Z80.  Replaced all row 6 ROM sockets, Z80 socket and the 285 socket.  Board finally showing signs of life.  Surprisingly row 4 RAM humming along.  FPGA confirms RAM/ROM.  Solder bridge found at 8H – might have been the original reason this board was deemed a parts board.  Replaced a faulty 74LS75 at 3D. Board now works!
Board # 4		Status upon arrival:  DOA. Repairs:   Board was  filthy and missing all of the row 6 parts and 5F, 7F.  Added back all missing parts.  Edge connector pads repaired.  Voltage steady 4.96vdc with crystal spot on.  Not much activity on row 6 due to many corroded sockets.  Replaced all row 6 ROM sockets, Z80 socket and the 285 socket.  All new 2532 ROM’s burned and Z-80 put back in place.  FPGA confirmed 2 faulty RAM at 4L/4K.  Board now works!
Board # 5		Status upon arrival:  DOA. Repairs:  Board was filthy upon arrival and missing many parts.  All row 6 sockets replaced along with the 285 socket.  Voltage steady at 4.94vdc.  All row 4 RAM good.  All new 2532 ROM’s burned for row 6 and row 5.  Game boots and plays.  There are missing ghosts and Pac as well.  Very difficult fault to find.  Turns out a solder pad was impacted at the un-populated location of D1 dragging solder to form a bridge.  This caused the missing ghost and Pac at D2.  Remember to always check for solder bridges and damage on these boards because of the long pins and fine traces.  Even check the unpopulated locations!  . Board now works!