Neotec NT-1431 (Medalist Dart Star monitor) pin cushion issues

Ok so that leads me back to the secondary of the pin transformer. Take a look at that jumper and see if it looks deliberate. There is just no way the PCC will work with a jumper across the secondary. However if the transformer had burned or opened up someone may have jumpered it.

It's very deliberate because I did it. I jumpered that because the pad had lifted. That was the nearest spot that had continuity.
 
Ok, that explains your pin issue. You jumpered across the secondary side of the pin transformer. The continuity you were reading is the secondary winding of the transformer. Remove the jumper. Fix the trace and you should be good to go.
 

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Ok, that explains your pin issue. You jumpered across the secondary side of the pin transformer. The continuity you were reading is the secondary winding of the transformer. Remove the jumper. Fix the trace and you should be good to go.

Ok, so where should I jumper to that's safe?
 
There's plenty of room there. Just scrape some of the solder mask back away from the pad. If the gap is small enough you can just make a small solder bridge. If not just use a jumper from the pad to the now bare trace.

I've got a small nylon brush that works well but a jewelers screwdriver can do the same trick.

If you have any concerns, post a picture when you're done.
 
The jumper between R428 and C417 is a bit confusing as it effectively bypasses the secondary of T403. Maybe the winding was open and someone did that as a stop gap?

I know you say you checked it but the picture really looks like there is a base to collector bridge on Q304.
Should you help with the entire schematics diagram for Neotec NT-1431. Thanks
 
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