jamma wierdness

[death69inc]

have a 60 in 1 friend bought and has me setting it up..
well 60 in 1 works fine plays etc . 

BUT no other board I hook to the jamma harness does only the 60 in 1 (BWT they all work fine on my test rig)
tested goldentee cps1 cps2 and few others nothing

tested voltage from his pc type supply 12v was running 11.7 figured wasn't to low but might be it so put it on a good switcher still no go, all voltages are good. and 60 in1 running off switcher now nothing else .

checking all jamma harness pinouts etc all seems good video ground was not connected at 14 was wired into ground cluster so I wired it to 14 just in case no help.

just weird to me

he wants to be able to use other jamma boards in this rig .......





 

[johnrt]

Have you checked the voltage on the JAMMA board itself in addition to on the PSU. You may be a victim of bad power wires on the JAMMA harness resulting in the voltage drop being too high. Remember that original boards draws a lot more current than the xxx in 1 boards.

[death69inc]

well with his pc type supply I get 11.7 -5.1 +5.1 at supply at board 11.6 -5.1 +5.0
didn't not check board voltage with switcher will have to hook it back up.
.1 drop when switcher was reading perfect shouldn't be that bad will see maybe needed to turn it up a little to compensate for drop. never did like these type of jamma harnesses Zjamma 56p-3.96s.

[death69inc]

turned out to be just that bumped up voltage a little and it fired up
not sure why I didn't check voltage drop to board brain fart ... but since switcher worked with my harness I knew voltage was fine but didn't think about dif harness dropping voltage more or less shrugs live and learn.