First fault finding

Back to the mysterious flipper firing together with the lamps, when all the lamps were on and flashing.

My first guess was that there must be some kind of cross talk on the power board and so was just about to check the circuit diagrams to see how on earth that could be happening, when I thought I’d first check to see if the problem also happened when the left flipper switch wasn’t connected. It didn’t. So could there also be some sort of cross talk with the switch wiring, somehow? Then I discovered something very curious…

The interrupter for the opto flipper board was slightly misaligned to the opto switch, this made the flipper switch very sensitive. On aligning the interrupter with the switch manually, the flipper no longer activated together with the lamps. So it would appear that the current drain from all the lamps being on at once affected the threshold of the opto-switch ever so slightly, so that it then switched, because it was near to its switching threshold anyway (due to the receiver receiving light from the transmitter even when it was supposed to be off) thereby firing the flipper bat.

Unfortunately trying to physically bend the interrupter into shape didn’t work. In the end I switched the left and right opto boards and the problem was solved.

Job done.

Leave a Reply

You must be logged in to post a comment.