Thank you both for the 'heads up'. I'm going to open this post with my closing statement: I am going to buy a new SDU board. My question is should I buy the Altec board, or should I get the the Rottendog unit? The Altec is approx $50.00 more. Is it worth the extra half a yard? I'm all ears.
You two sent me off reading and researching.
I came of age during the era of small block '57 Chevys and big block Corvettes. Labor was too expensive to farm anything out so you learned to do it all. Sometimes it worked out and sometimes (expensively ) it did not For better, or worse, that mind set still lives with me today. I went at the burnt board. It may have turned out for the worse
SIDEBAR: I bought this Big Game on Thanksgiving and had perhaps 10-12 hours of relative trouble-free play time before the slingshot coil shorted out. The only reason I went after the board is Steve Young @PBR said I needed to replace the transistor, as well as the coil.
To get working space, I removed 4 drivers, 4 caps, and 4 resistors. As you advised, I cleaned the area with alcohol. With the affected area now being visible I could see that the burn went almost through the board. Luckily, it did not burn through and the traces on the backside remained intact. To repair the burned area I used chopped fiberglass fibers and fiberglass resin. To help seal the area around the burn I spread out a light coat of resin.
I got my replacement parts from a local electronics shop that has been in business here for 50 years (they sell everything that Radio Shack doesn't sell). The drivers are the TIP102s. I forgot how to read the ID bands on the resistors but the old gray haired shop tech said the blue ones are the correct value (I hope he was correct).
Here is the repaired area.
IMG_0439_(resized).JPG
Here is the backside---post repair work.
IMG_0444_(resized).JPG
I reinstalled the board and fired up the pin. It played fine----for two 5 ball games. When I hit the credit button for a third game, all I got was a chirp from the speaker and nothing more. Now my pin is deader than a door nail.
Here is what happens: I turn the switch on. The displays light up and flash the way they are supposed to do. Attract Mode kicks in and the table lights all start flashing. I hit the credit button and just as the machine goes dead I hear a small click in that relay on the SDU board. And this is where I am stuck. I don't know how to troubleshoot this. This relay is trying to tell me something but I am at a loss.
Oh, and I noticed one other thing: 5 of my play field lights are not lighting up in Attract Mode.
So, I changed 12 items and got two good games going. Did I do something wrong or have I ran into some other coincidental problem? The thought of just buying a new board starts to gain some traction i.e. it might be cheaper in the long run
Anyway, I pull the board to double-check my work and finally notice something has been done on the other end (sometimes I suffer from tunnel vision). I get out the magnifying glass. Keeping in mind that I had several hours of good gameplay with this board, I see that 2 drivers have been removed. A check of the drawing shows one of the removed drivers being located in an open slot at the connector. I don't know about the other driver, yet. I continue looking with the magnifying glass and see a solder joint that looks like it cracked and fell off.
Here are the pics. This shows the position of the two removed drivers.
IMG_0455_(resized).JPG
And this pic tries to show the missing solder. This pic was taken with an iPhone looking thru the magnifying glass. The solder has cracked off all the way around, though it looks like there is still some contact.
IMG_0456_(resized).JPG
Anyway, I want to play my pin so I will get a new board. Should it be the Altec? Or the Rottendog?
If this problem goes away with a new board then I will know I blew it somewhere. If I can eventually isolate what I blew up then I will have a spare board.
And if the problem persists with a new board, then I will know I got hammered with a coincidental problem that decided now was the time to rain on my parade.
Sorry for being so wordy. Thanks for managing to read this far.
I plan to keep this Big Game for a long time. Which board do you all like? Altec? Rottendog?
Any ideas on what I did wrong?
Thanks.