Ok, Ive got the schematic from Pinballfixers site - thanks mate!!
I dont have the manual so its a bit hard for me to follow whats going on here,
Let me get this straight - F1 keeps blowing, this is a 5A Slo Blo.
transistor that keeps blowing is Q1, this happens at power up, but you can hear a hum?
No its the F9 which blows instantly on power up - it is a 250v 5A Slo Blo. On a quick side note, I could not get an identical one from Middy's ie the wire in the middle looked different however it is a 250v 5A slo blo glass fuse
Now with your DMM set it to 200ohm setting ( this will probably be the least resistance value on it), check diode D21 on the PPB. It should read low resistance one way, switch the test leads over and you should get infinite ( will go off the scale) reading the other. if you get low both ways, this diode is short.
I'm not a whizz with the multimeter I set it to OHM changed the range to M. It read 1.184 one way, then .OL the other. Not sure if I did this right.
The feed in to Q1 is connector J8 pin 11, - out is J8 pin 12. make sure there is not a short across these.
Checked these, nothing obvious and looks OK.
Also R19, put meter to a higher reading and you should get 220 Ohm ( or VERY close).
measuring resistors in circuit can be decieving though and sometimes you have to lift one leg.
Yep, one leg sore back now...On k OHM setting read as .220 / .221
Make sure TIP36C is in the right way round.
Yes is identical to others.
If you do all this and this checks out, then the circuit for this transistor is fine and we need to look elsewhere, but lets eradicate this first
I tend to think it has something to do with the violet / yellow wire, which is used on crane (flashers I think) and the magnets. The humm on power up I am convinced is the magnets. Even with new TIP36C with magnets installed, fuse blew - even with coil unplugged and killed my new Q1. No sparks under PF, no obvious signs of a short / exposed wire although could be difficult to trace...
I removed fuse from magnets, unplugged both sides of the aux board - 520-5068-00 which violet / yellow goes into...Powered up - fuse fine nil blow.
I cleaned the aux board in a tonne of alcohol and observed 3 dry joints...Two on J2 plug and one on the middle transister. I have not put it back in again as I dont really want to blow another Q1. I am googling to try to find the transister values for the aux board (P20N10). The joints have been repaired. The board has been previously repaired as there are a couple of track repairs but they look clean..
Its becoming a riddle, but I am extremely grateful for your advise and the time you guys are spending to help me.
I have certainly crossed into territory which is new, but also exciting as I never thought I would be able to repair a board (well PPB only at this stage)
