by kra on Mon Nov 28, 2011 5:39 pm
Hello, I'm looking for advice repairing my Elvira and the Party Monsters machine.
I had a sticking right flipper. Disassembled and found that the flipper solenoid was bulging and binding the plunger. Replaced the flipper coil. Game worked for about a week, then the right flipper stopped flipping.
There was a blown fuse, and a flipper coil diode (between one of the coil legs and the shared coil leg connection) wasn't dioding. The coil itself was OK according to my ohmmeter (after the diode was disconnected).
Replaced the diode, checked it and the coil. Replaced the fuse. Started a game and hit the right flipper, at which point the fuse immediately blew again. Flipper did not flip, and new diode is now also gone.
I assume that whatever first broke the flipper fried some semiconductor device in the flipper circuit, and as a result whenever it is powered there is a short of some kind, which is wrecking the diode and blowing the fuse. It's possible I didn't properly set up the end of stroke switch when I put the new coil in (it was set up properly before I tested and blew the fuse the latest time).
So, I assume that some or all the devices in that circuit will need to be replaced, if they still exist. I have the manual, with circuit diagrams, and can hopefully find out what those are, but I'm wondering if anyone has any hints about what to look at. Is there something that would be causing this problem that can be tested? Is there something I should look at first? My worry is that I'll think I'm replacing everything relevant, blow it again, and need to start over. I don't know much about EE, but I can use a multimeter.
Thanks for any help. -Karl