System 80b behaviour

[Topher5001]

My Raven is getting the tilt switch closed error so I replaced Z10 thru Z15 & U4 but I'm still getting it. I disconnected A1J6 & A1J4 for testing. I still need to do the slam tilt mod so I can unplug A1J5 also.
When I disconnected A1J4, the helicopter spins continuously. I don't remember this happening before. Does anyone know if this is normal? If not, where should I start looking? A short somewhere?

 

[sylvain]

In cases like this, using a logic probe is a strongly recommended procedure before replacing any chips
- to detect where the switch strobe(s) and return(s) might be wrong or stuck on the MPU,
tracing back from the U4 6532 RIOT input pins, outputs/inputs of the 7400 Z13 & Z14 to start with...
I assume you already have the manual/schematics? Another must...

Good luck!
- Sylvain.

 

[Topher5001]

Yep, have the schematics.
Adding the ground mods & popping chips in & out of sockets is the limit of my board repair skills. I thought that since the helicopter spins when A1J4 is unplugged, that there may have been a short. I'll do the slam tilt mod & call Al I guess.
For the record, here's what's been done:
The trim pot & LM338K were replaced on the PS
The cap & rectifiers were replaced on the transformer
The ground mods were done
Most single-sided connectors were re-pinned (I think I still have 2 to do)
Z10 thru Z15 were socketed & replaced (Z12 fell apart when removed)
U4 was socketed & replaced
When I replaced the rectifiers, I was careful to label the wires as at the time I wasn't familiar at all with schematics. It ended up I had two wires incorrect, although it worked for 6 months like that, & I had a crappy soldering job on one wire. When I replaced the Zxx chips, it did boot, but there was no GI & it would coin up but not start a game. I went into the tests & everything was okay.

 

[Topher5001]

Al came over yesterday & got it running. He saw what colour wire the tilt was & just pulled it out of the A1J6 connector. No tilt, but it plays.
He's going to bring a sound board over & see if he can get the sound working. Right now it's all over the place. Gameplay music all the time, constant explosion sounds & sounds I've never heard before. It also reset twice during gameplay last night. I'll ask him about that too.

 

[Menace]

Do you know if any of the connector pins have been replaced in the game? Ground mods done? If not, I would start there...

D

 

[Topher5001]

Yes, the ground mods have been done. I've re-pinned most of the single-sided connectors, but I'm leery of the double sided ones. I'd have to reuse the housings & they look like a bear to work with.
What else has been done is in post 3.
Before Al pulled the wire, I'd still get the tilt switch closed error even after unplugging A1J6, so I think the problem's still with the MPU. The sound problem, I don't know about.

 

[Menace]

You can mod the tilt section of the MPU, if it's the slam tilt that is causing the problem. (I think sys80B is the same as sys80)

D

 

[Topher5001]

I was going to do the slam tilt mod, but that works okay. I was getting the 'tilt switch closed' error, even after unplugging A1J6. Al pulled the tilt switch wire from that connector & now it boots.
Another odd behavior is the GI goes out when it's not supposed to. I have no idea where to begin with that. Next time I talk to Al, I'll ask him about. It maybe something on the driver board. It's been happening all the time now. It used to happen only occasionally.

 

[Menace]

Where the game works with the wire pulled out of the connector, the issue will be out in the game and not on the PCB so changing the IC's wouldn't fix the problem. (if it was a PCB issue the problem would remain even with the wire pulled)

GI going out at random? Sounds connector related to me.

D

 

[sylvain]

For the GI - check the Tilt relay contacts under the playfield - and its drive (coil) from the connector/driver board.

 

[Topher5001]

Thanks guys. I couldn't find out too much info about the tilt relay. I had wondered about that. I'll look into it.
Actually, Al messed with the tilt relay to get the GI working. The problem is that it goes out when counting bonus or in attract mode when the inserts do the chase towards the bottom & it goes "Pew Pew Pugh (explosion sound)"
The AC seems low. On A5P1 pin 6, I get 7.5vac when it should be 12vac. I also remember checking the output of the bridge rectifiers on the transformer & if I remember correctly, it was low there too. I'll have to check A4P1.

 

[sylvain]

Hmmm, is A5 the Aux. Power Supply? If so, and if like Gold Wings, A5 is used only to supply the sound board
and it has nothing to do with the MPU, solenoids or tilt/game over relays...
In those games, both relays under the playfield are operated like a solenoid, e.g. 24VDC when the coil is activated.

For the AC measurements on aux power supply A5P1 pin 6:
you should measure 12VAC between A5P1 pin 6 and A5P1 pin 7 (and not in reference to ground).

Update: Intermittent drive issues are often due to bad/corroded pins in the MPU-Driver harness.

Did you perform the ground mod "power supply-MPU-Driver board" (Including the driver board) ?
Another ground mod method for Gottlieb Systems 80-80A (I think it might also apply to system 80B) is the one suggested by Todd of TNT Amusements, for MPU-Driver:

- Sylvain.

 

[Topher5001]

I'll check that voltage tonight.
I ran grounds from all the boards to the ground lug at the bottom right of the head.
I haven't touched the harness. I heard that the Molex crimps 08-52-0072 don't fit properly & I don't have enough bifurcated crimps to do the whole harness.
I'll watch the video when I get the chance (I'm at work).
Thanks for your help.

 

[Topher5001]

I checked A5P1 pin 6 to pin 7 & got 13.1v AC.
I had previously checked A12J1 on the transformer panel & I got:
Pin 1 (6v AC Return) 5.1v AC
Pin 4 (6v DC) 10.4v
Pin 5 (27v AC) 18v AC
Pin 6 (27v AC Return) 14.9v AC
Don't know if that means anything.
When I re-pinned A6P1, I did it one wire at a time so I wouldn't get confused. The schematics show all the pins having wires except for pin 10. Mine has pins 4, 6, 7, 10 and 16 open. I guess they're not used on this game.

 

[Topher5001]

I took the boards out so I could replace the stand-offs. While they were out, I added the 5v DC & logic ground wires to the MPU/Driver board harness. Lamp 9 at the top rollover & L47 were both out, so after testing I re-flowed the solder on Q10 & Q48. L9 works now, but L47 doesn't. I think Q48 is pooched. Next, figure out the GI & then get the sound working.
Eh, just noticed that neither flashers are working. Ugh.
Never mind. I hadn't plugged A3J6 in. Duh.

 

[Topher5001]

Was playing last night & the GI behaved as it should. It flickered a bit when the inserts chased & the flashers went off, but it didn't go out. I had taken A6P1 & A5P1 off to check my re-pinning. Maybe that had something to do with it. I'll wait & see how it behaves tonight.

 

[Topher5001]

Working perfectly now except for sound. I'll start another thread.