New Happ/Arcadeshop Power Supply issue

cowboy255

Member
Joined
Sep 2, 2010
Messages
103
Reaction score
1
Location
Baltimore, Maryland
I got a brand new Happ switching power supply with the Arcadeshop adapter for my Stern/Konami Super Cobra. The game was running well enough with the old PCB power supply board but things were getting glitchy so upgrade PS time.

Problem I have is adjusting the new supply. Initial under load measured +4.8v but way over on the +12, which measured 14.3V. Even adjusting down and bottoming the supply out to +4.3V I barely got the +12V end down under +14V to +13.8V. Obviously that isn't gonna work out.

Bad switching power supply? I measured at the PS outputs and got near like readings on the multimeter. Set dead on at +5V the +12 output was way high near +15V.

Suggestions?
 
that's fine. Your +5 is what is important. I've had PS run the +12 that high and the board works just fine. Usually the +12 is there for the sound only, although I know a few boards use it elsewhere...
 
not really a scholar on the subject (despite my PSU guide :)) but wouldn't the +12 go high if the +5 isn't getting through well enough to the board? I can't stress enough under ALL circumstances how important it is, just for fun, that your edge connector be clean.

that said, the +5 coming out of the power supply is not where you want to measure, it's much better to measure at TTL components or even a rom on the board to know what your voltage needs are exactly.

assuming the U-shaped notch on one of those chips is on the left, you want to use your meter probes on the upper left corner and lower right corner to test for +5.
 
Back
Top Bottom