Zaccaria Solved Pinball Champ (Zaccaria, 1983) power problems

[jimmy's machining]

Hello all, Jim here.
I just brought a zaccaria pinball champ 1983 model. after power up all that happens is some globes light up and that's it.
I have done tests but am now stumped
all input voltage to the powers supply board is good.
then I tested the test points with these results.
TP1 GOOD
TP2 BAD
TP3 BAD
TP4 BAD
TP5 GOOD
TP6 GOOD

from what i read if the tp2 12v is not right then the 5.6 and 5v won't work because they feed from the 12v... not sure what to do next, I think it's something on the board to do with the 12v but not sure what to look for or how to fix it.

any help would be highly appreciated
Cheers Jim

 

[pinballdaveh]

the voltages at TP2 and TP3 come off a bridge rectifier. the voltage TP4 comes from a different bridge rectifier. unplug machine , unplug all power supply jacks, remove power supply board. on underside of board check and or re-touch solder conections on connector pins, rectifiers, and fuse clips. check fuse clips for holding strength. test and check fuses for correct value. install board back in machine. only install input jack, turn machine on and test voltages at test points. write down findings.turn off machine, install all output jacks, test at test points again note any differences.

 

[jimmy's machining]

Hello pinballdaveh,
I have done as you said and got the same results with the harnesses connected and disconnected, there were a couple of tenths of a difference here and there but i'll type my results if needed. re soldered a few points that looked like they had some corrotion around the outside of the solder, changed fuses etc. now on the powerboard i tested the bridge rectifiers and noticed that the black one that is in curcuit with the 16v caps seemed bad and a storeman at our tafe collage agreed but suggested I remove them and check, the two grey ones seem good but the black one seems better out though measuring one way + or - (can't remember) the values were just over 600 which the youtube video I watched said they should read from 400 to 600 when set to diode on your multimeter.
I'll add the results just incase
tp1: 163v
tp2: 0.3v
tp3:0v
tp4:2.3v
tp5:37.4
tp6:-5v
tp7:1v

 

[jimmy's machining]

phhhheeew, it turns out it was one of the fuse posts, I am up and running now only problem is the sound, the speaker hums. sometimes you can slightly hear the sound and for a brief moment after a sharp skillshot it worked normal

 

[pinballdaveh]

congrats on getting your machine working. speaker hum is usually sound and speech board electrolytic caps going bad . i didnt see any cap kits for zaccaria . there is quite a few 100mf caps on this board. this value cap has caused trouble on other boards. those would be the first caps i would change.