Here we go again... found this Chopper that's been sitting for at least 20 years.
Tearing into it, I was pleased at how relatively simple the game is.
Couldn't find much info, my serial is #344 and the few other ones I could find were all under 500 so guessing 500 were made.
Reading the pinrepair the downfall is that while it relies on a lot of common solid state components, some are discountinued/unobtanium.
Gameroomrepair.com has an EXCELLENT 4 part series on youtube going over the major aspects of the game and how everything functions -
Here's the main schematic: https://drive.google.com/file/d/1HL30R8ygmuofGh97RDPFAraTXuMeCSiz/view?usp=sharing
Logic schematic: https://drive.google.com/file/d/1Uh3fLVIDS54TyDoJxI0V94LuN4fInrsb/view?usp=sharing
Parts catalog: https://drive.google.com/file/d/1qohdY5_pIby0w6M6FhzyVD1r3IA6jAdt/view?usp=sharing
Good news:
It's complete!
On top of that, there's an extra display/logic board, an extra photo sensor board, and an entire extra target motor assembly.
Cabinet shows its age, but is solid and in relatively good shape
Glass is all clean with no scratches
Rear lithograph is there, some UV fading from the bulb at the top but overall excellent shape! I scanned it all for backups.
It fortunately comes apart in a few pieces allowing me to fit it into my otherwise small entrance basement!
I even found the perfect spot for it tucked under the stairs.
Bad news:
The logic board that boots, the displays are shot
The other logic board has good displays, the game doesn't start
Motor 2 isn't moving up or down, the TIPs diodes and transistors all test good, ordered the last cheap UA741HM driver on eBay
4/5 of the target sensors were testing out of spec
The 8 track deck is missing
So far I got the game mostly going, cleaned and adjusted some switches, replaced some large capacitors, the chopper works, 3/4 of the motors work.
I will be replacing the 8 track with an Arduino.
The logic board with the good displays will have to be repaired, in the meantime the one with bad displays is fine for testing.
The spare motor target unit has a good sensor so have been using that to test the photo sensor board.
Ordered some GL5528 photoresistors on eBay (10 for $5). That with a 200 ohm resistor in parallel creates enough resistance to trip the circuit!
While gameroomrepair.com has some NOS ones on his site for $22/unit, glad I was able to make something work for cheaper!
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