In a previous post I had an issue with the ball kick out coil. I replaced it along with the transistor at Q32 on the driver board. The game has been playing great since.

Recently I've been blowing the 2A fuse that covers three banks of drop targets, green, red and blue. Just before the fuse blows the machine makes a screeching sound that doesn't stop until the machine is turned off. Once the power is cycled the game boots and the fuse is blown. The game will start, ball will kick out but the drops will not reset.

I can replace he fuse and get a lot of plays out of the machine, but then it fails. I would like to fix this permanently and not have to replace fuses so often.

These targets are controlled by the same driver transistor from what I can tell, Q32. I had to replace the transistor with a NTE261 which cross referenced as a replacement for the original 2N6043. Given the specs of the NTE transistor is not identical to the original I am wondering if this is now my issue.

Any thoughts? Should I be looking elsewhere for a different root cause.

Prior to the lockout coil burning up the machine played without issue. No shorts on the driver board currently, but something is messed up...

Left the machine on all night in attract mode and it started squeaking and the fuse is blown.

Gottlieb Countdown system 1 with original driver board.

I may have found the issue. It seems that the original transistor may have been replaced with an incorrect transistor, leading me to further replace with an incorrect transistor.
I picked up a NOS board to be safe. So far, so good...