Hello again got a problem with my demoman pinball all the coils except for the flippers are weak! For example the ball launcher isn't able to drop the ball and if i drop a ball in the upper-right hole the coil is too week to pull it out

I have tested the power board TP points since looking on the web the problem could be here.. these are the results:

TP1=13.3V (should be 12V)
TP2=5V (should be 5V)
TP3=12V (should be 12V)
TP6=68V (should be 50V)
TP7=1V (should be 20V) !!!
TP8=15.3V (should be 18V)

As you can see there are clearly some problems, but I really don't know where to look for the cause!

I have also tested the power on some coils --flippers are 43/45v and the ball launcher 63/64v

What do you think of the results? Any suggestion on what to do?

Thank you!!!!

Hello kvan99 already tried that way but no changes! :/ today I will try to put on another power board, took from my bride of pinbot, and see what happens!

Changed the power board and now it works greatly!
I have also tested the TP on the working board to see differences and here are the results:

TP1=13.5V (should be 12V)
TP2=5V (should be 5V)
TP3=11.8V (should be 12V)
TP6=68.9V (should be 50V)
TP7=20.5V (should be 20V) ----> as expected this seems to be the major difference
TP8=15.5V (should be 18V) ---> what does this 3A difference means?

now..how to detect the problem on the old power board?
I was thinking to change bridge rectifiers BR3-BR4 cause some friends told me that are usually problematic but i don't really know '^^

any help is accepted!

Thank you guys! Which bridge you think I have to test? There are five of them! I guess i'll have to desolder them..but how can I perform a correct test? I'm new to electronic This is my multimeter, which mode should I use? And where do I put the pointer to test the bridge?

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Hello guys! I've tested the bridges as suggested on the pinwiki guide! They seems to be all good all the values are around .6 (the working range is from .5 to .7).. Maybe the problem is elsewhere.. I show you some pictures.. Maybe they can be helpful! As you can see someone did some (imho bad) works on it!

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Sure! They're all ok! I've replaced 1 which was shorter than the others but still worked..

Hello everyone! I'm back on this topic with news! I have changed c8, c11, BR3 and BR4 but no success! Now the coils don't work at all except for the flippers! Tp6 and tp7 measure 0 and led 5 is always off! Also the flashers are off any suggestion???

Fuses checked. All ok.

Grumpy you're on the good way..i checked the continuity between pin connectors, bridge rec. and capacitors and in some cases there were no connection.

It seems that the solder is not able to pass through the other side of the board and completly cover the bridge legs..
how am i supposed to do? Even adding more solder it doesn't seem to go through! It just stay on one side and form a bad ball shape joint..

Problem solved! Several traces were off and I recreated them with little pieces of electrical cables. Now everything is great a part of a strange smell of burned plastic! How can I be sure that cables will maintain?

I have found the problem!
Pin 12 of J115 connector (GI) was starting to burn and melt! It doesn't seem to be connected to the previous repaired circuit but what is causing it's burning??? How can I repair this thing? This is an infinite story!!! Thanks for your help!

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I didn't noticed a cracked solder joint here..I hope that once replaced it won't burn again..and also I hope that it is not connected to the previous reparation..any suggestion, advice or warn on replacing connectors?