I've been watching this club anxiously awaiting for my baby to arrive. Finally I got one, snagged from a stale Facebook ad I just happened to inquire about!
I made a deal I know this thread would drool over! Bundled with my Baby Pac was a huge spare WORKING board set including 1 Vidiot, 2 extra MPU's 1 extra solenoid driver board, a different Bally lamp board (for parts I guess?) as well as a Vidiot Deluxe for Granny and the Gators (I can dream)
It wouldn't start a game when I bought it and many lamps were locked on.
Got it home after a 10+ hour round trip (should have only been 7... how foolish I was!) and it started almost no issues.
First only the bottom switches worked.
Then the flippers died and only the top half worked. I finagled the connectors, which he said he redid the problematic ones J1-3 and most the playfield bar the right saucer worked!
Xmit 40 kept failing and turns out J1 pin 27, I believe, broke right off completely when I investigated. Thankfully the seller also gave me a complete connector kit with tons of spare connectors and pins!
Honestly most of the IDC connectors are fine and give me no issues, I suspect oxidation on the pins after many years caused the flakey connection errors. Worked them through and now it's playing well!
Tons of lamps were dead or locked on. P C A and the energizers were stuck on. As well as TUN L
The solenoid board he had in there is garbage as it seems. Over half the transistors must be blown. The spare he gave me is nearly flawless!
My one persistent issue is that TU N L and the left arrow are still locked on and this persisted for both boards. And I know you're probably not supposed to do this but I unhooked the solenoid/lamp board completely while it was on to see what would happen and with the board completely unhooked those same lights (TU N L & Arrow) still stay locked on!! I suspect there must be some weird short somehow keeping them lit since they stay on without a lamp board.
Although for sure Q30 is dead on the good solenoid because the very last row the A and energizer is out and it works on the crappy board that locked everything else out.
So all lights are good. I looked at the schematic and noted that Q 2 and Q 4 are responsible for the TUNNEL and arrow that stays on. But I don't think it's the transistors as I said that are causing it as it persists with both boards. And the U is extremely bright and flashes at half brightness. Very perculiar...
If any guru out there can offer suggestions I appreciate it! Be detailed as I know some electrical board related things but others I'm clueless about.
Also I don't have access to a digital multimeter but I have a analog one. So if someone knows how to test transistors with an analog meter I'd greatly appreciate it!!
My last question is advice on the playfield.
This Baby Pac is special because it belonged to the legendary Fun spot in NH! It even has tokens from 92, 96-98 in the coin box! So the game does have some wear in spots but it isn't terrible in my opinion. And I believe it has Mylar on it but again I'm not too sure about some of these things.
It has white specks and what seems to be delamination but I'd like to keep the playfield original and touch it up and protect it on a budget!
Suggestions of all kinds appreciated! Oh and if anyone has some LED suggestions let me know because I'd really like to LED this playfield and lite the "apron" Mr & Mrs Pac but I don't want to drill new holes, so what's the easiest way to tap into an existing socket and light those guys?