I have a problem that has been hard to track down. All of the controlled lamps on my game are not lighting up, or at least not bright enough.

When I look to see if there is 6VDC on the lamps line (metal braid on playfield), I instead see closer to 3VDC. I can also see evidence that the bulbs are actually sort of working, but them seem really dim.

I then looked at the Bridge Rectifier that controls the AC to 6VDC for the lamps ( in the cabinet). It appeared that it was low on the DC side, but once i removed the wire from the bridge rectifier on the DC + side (to separate the rest of the wiring from the equation) it tested at 8VDC (certainly enough to power the lamps).

What would be the next thing to test, to try an figure out why my voltage is dropping so low from this 8VDC?

Thanks!

Chris

I think the power supply side is good, as the AC going into the bridge rectifier was a good 8VAC.

I will look around for connectors after that point though, as that does seem like a likely way that voltage could drop that significantly.

It appears that the controlled lamps going to the backbox are also very dim (high score to date, game over, etc).

I will try this today.

Thanks Inkochnito.

Chris

They are all about .47 volts, so it does look like the BR is ok from that test.

Chris

Coin door looks good.
I tried to bypass the tilt relay altogether, actually, though it seemed to be working fine, and i did clean it as well.

But just to cut down on the variables, i am bypassing that switch to pass the 6VDC to the playfield, directly, and where i want it.

I unsoldered the point where the metal braid for all the controlled lamps gets its power from the 6VDC. I am using alligator clips to test things currently.

Under no load at all, the voltage measures 9.5 VDC. Certainly looks good enough to get things lighting up.

But, as soon as I try to just add one bulb lit up, the voltage drops way down to 2VDC or so. Also, that bulb that i lit up is pretty dim.

Is it possible that my Bridge rectifier could be providing 9VDC but failing to keep that voltage once any load is put on the circuit?

I think i'll order some BRs regardless, and swap that one out to try.

thanks for your help so far.

Just wanted to close the loop on this one, in case it ever helps anyone else.

The bridge rectifier was indeed the culprit. It passed all the tests I threw at it, and tested fine when not under any lighting load. It showed a good diode test.

Once the lights were plugged in the voltage dropped from about 9 volts to about 1 or 2 volts.

Thanks again for the help, guys.