You can also get them from Digikey

http://www.digikey.com/product-detail/en/IRF9Z34NPBF/IRF9Z34NPBF-ND/811960

and anything over $25 your less than a $1/per...

Plus if you really want to cut down on more heat, replace the TIP41's with IRFZ34NPBF's.... They are the 'NPN' version of the IRF9Z34NPBF (just like the TIP41 is the NPN version of the TIP42)

http://www.digikey.com/product-detail/en/IRFZ34NPBF/IRFZ34NPBF-ND/811724

Welp, they got some in right. Don't that count?

One difference, look in the upper right corner while holding the 40 pin connector up... You'll see that instead of resistors on the switch matrix, they used 0 ohm jumpers on the system 7 board. This is one change to make the switch matrix more responsive.

You'll want to match a 7 with a 7, but I don't think you HAVE to. If you don't then you could get intermittent weirdness in the switches.

And if anyone is interested, yes, you can do the TIP42/Resistor -> MosFET/Jumper mod to the Hyperball specific driver board to cut down on a lot of backbox heat and increase reliability.

A before and after shot....

800px-HyperBallSpecificDriverBoard.jpg
20140522_154826.jpg

Back in the module repair depot we used to have these board sized temp sensitive plastic sheets (kind of like a mood ring) that we would lay over the board and connect a power source and it would light up as the area got warm. Maybe something like that? Or a thermal camera?

Barring that, you are going to be cutting traces me thinks.

Got a stronger supply?

Crank up the amps and see what glows.

Vid is correct.
Which is why it is called an "unregulated" power supply.

A regulated supply would have a ummmmm regulator in the circuit that would be watching the output and compensating for the load change and resultant drop.

The 12v supply in B/W games is a good example of an unregulated supply. When you add mods you need to watch the voltage so that you do not pull it down too far and cause weirdness.

Right off the top, those appear to be original caps. If this was mine, I would replace them before I even lifted a meter or troubleshot anything. It really is not worth my time or effort otherwise.

Those two vertical black caps are the exact same, just orientated opposite polarity. Both are 100uf

https://greatplainselectronics.com/categories.asp?cat=75

Go there, find the kit. Change all that are in the kit. If GPE is out of stock, Ed does list the contents and you can order individually. You will come across one cap that is out of stock causing that kit to be out of stock, for that one simply go higher in voltage as a sub.

New caps are VERY VERY rarely bad. Double check the polarity of the caps you replaced. We've all put one in backwards at least once (maybe twice but I aint talkin).

If they are all in correct, disconnect the output to the flash/sols. Does the fuse still blow? If no then you need to look off supply and maybe you shorted something lifting and lowering the playfield.

Really nice write up and homage to this thread. Thanks.

+1

And the Power Supply would have a GI relay mounted on it it it were a 7. Instead of mounted off board.

Exception is Black Knight is one machine that came out using a Sys 6 P/S in early units (transformer in head with GI relay in head) then swapped to a Sys 7 supply (transformer in body) for rest of run.

Or you are tilting? With game started, can you thump the side of your fist on the playfield and not Tilt? Can you slap both flippers and not Tilt?

Sigh,,, I did not mean you were abusing the machine to make it fail, I mean CAN you do those things to cause the problem.

That would indicate that a slam switch is adjusted too close and the solenoids movement is tripping it.
Or that multiple sols firing at once was dipping the watchdog timer threshold on the cpu.

Sorry, other life stuff been pulling me away from pins. You did not mention what game you tried this on. AFAIK anyone who has done this on Williams has had no issues, but there were some issues seen in DE, There was a thread about that somewhere where the fix is to add a small value resistor back into the circuit.