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I'm digging through all the things I've found to be wrong in this F-14. Can you spot the issue? #pinball #pinrepair
@apzpins so why would you put a diode between the cables and then also seemingly close the circuit across the metal plate? Is this just a classic case of stupidity or am I missing something?
@alto The circuit looks like this: power feed -> coil -> drive-transistor -> ground.
To drive the coil, it's grounded. The diode directs the power spike from de-energizing coil from going towards the transistor, which can't handle it.
The diode is upside down, which makes the path of least resistance skip the coil, so now the path is: power feed -> diode -> drive-transistor -> ground, effectively shorting the power feed directly to ground.
Lots of things become very unhappy at this point.
@apzpins I see, well then it wasn't quite as obvious as I thought :D
@alto Here's how it looks, with the part in the picture highlighted.
