Help with board work

[beaky]

I have inspected the above remarks and find them completely legal. 

I am surprised that it would even boot at 3.64V 
sounds like a capacitor problem but could just as likely be a bridge fault.
even if it is the 5 volt reg if the original caps and bridges are still on the board the are due for a change.

If you have inspected the header pins and connector housings on the relevant connectors and, found them in good condition, with no brown scorched areas on the housings, and the wires are seated in the housings properly and they all seem fine, then the connections shouldn't be cause of the fault.

you can remove make sure that fuse F113 looks ok and has clean metal caps on both sides, then make sure the fuse holder clip surfaces look ok, when you re fit the fuse make sure it is sitting in the fuse holder nice and tight, if the fuse slides left and right really easy or one of the ends is sloppy then this could also cause problems.
The fuse holders on these boards are pretty good in general but i do find a loose one from time to time
 

I don't think its a varistor problem for the same reasons mentioned by DSB
Happy to have a look at it when i am in Brisbane next.


 

[mickthepin]

All fuses and connectors good.
I read somewhere that I should test C4 but my DMM doesn't  appear to have microfarads on it.

[Homepin]

All fuses and connectors good.
I read somewhere that I should test C4 but my DMM doesn't  appear to have microfarads on it.

It isn't that simple - accurate testing of caps can't really be done using a multimeter - the best test is by replacement with these things.

[DSB]

Most DMMs don't test capacitance. You can by a capacitance meter for who knows how much and you will have to remove the cap from the board to test it but capacitors are so cheap that if you did that you may as well replace it. Your problem could be C4, C5, Bridge rectifier BR2 and maybe but not likely the LM232 regulator at Q1. If you have the board out I would start by looking at the tracks on the front and back to see any signs of poor previous work or bad solder joints. You could use your DMM to test the resistance between the components. Check out this site for some good information. http://www.pinwiki.com/wiki/index.php?title=Williams_WPC#Game_resets Go down to 4.8 game resets.

[beaky]

I test the caps with a dedicated capacitor meter after I remove them just for curiosity sake but I will always fit new caps after remove them. When the caps are that old it's time to replace them anyway
Testing the caps with a multi meter by checking how much AC voltage there is can prove that the cap is faulty but can't prove that the cap is ok