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Here's a weird question for the ARII folk on here, had an ROTJ on the bench recently, and it came with it's original ARII (identical serial numbers). The board had logic faults that are now fixed, but the owner sent the ARII as he was getting 0V on the 12v rail and he took this to be a sign the ARII was faulty too.

The ARII is a A035435-02 which seems to be correct, the cabinet only uses the -5V output, leaving the +12v, the +22V and -22V unused, as the ROTJ cabinet doesn't use 12v anywhere.

But on this ARII the 12V rail would never have worked, as the power resistor R25 has been fitted in the wrong location, it should be connected to the other pad to the left of where it is currently.

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With it fitted between those two pads there is an air gap in the circuit leaving C22, C23 and the 7812 isolated.


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In this location the legs of R25 are actually connected together, so it is completely pointless.

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The solder on R25 looks original. especially on the parts side ( the flash makes them look a bit newer on the solder side) but the most telling sign that this is original is the correct pad is is still filled with factory solder, even with the dimple from the wave solder bath. R25 looks identical to the power resistors on other ARIIs I have, where the legs are correctly spaced and installed to the right pads. So I don't think this was taken off and then put back in the wrong place, the legs aren't long enough, and they have the slight bend to aid placement still intact.

If this was an attempt to disable the 12V they could have achieved the same thing by leaving R25, C22, C23 and the 7812 out entirely, saving the cost.

When R25 is lifted and connected to the correct pad the 12V line lights up and the ARII will happily run my Star Wars cabinet, which needs all the voltages present on the A035435-02 variant.

What do you think? Manufacturing fault? Possible a dodgy batch used on a game where the lack of 12v didn't matter.
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