Area69
Active member
I recently obtained a Space Duel which had clearly been sitting for ages with the usual ancient and thick layer of dust over everything internal.
Overall in great cosmetic condition, only needs Simple Green to remove it's protective layer of nicotine.
Monitor has been replaced at some point with one from a Tempest, as I can clearly see Tempest burn. Matching serial numbers on everything but the PCB, so that's been swapped out at some time also.
Rather than plug it in and see what happens, like I would've done years ago, I uplugged the power to the monitor, and the two edge connectors, and tested the voltages at the AR2 after having a good look over.
Everything checked out as would be expected, with the unregulated voltages being higher and the 5v at the + side of C1 being almost spot on. Voltage to the monitor is 50v-0v-50v. I even go to the edge connector and checked at those pins, all good.
Next I cleaned the edge connector fingers with a fiberglass pencil, and then the various connectors on the AR2 get the Deoxit treatment, check everything again, all good.
So I plug the pcb back in, place my DMM probes in the 5v and GND test lugs on the PCB and hit the power switch, 7V! WTH!
I turned it off right away, but what the heck? How am I getting 7v on the board, whenever I just verified 5v from the AR2.
Overall in great cosmetic condition, only needs Simple Green to remove it's protective layer of nicotine.
Monitor has been replaced at some point with one from a Tempest, as I can clearly see Tempest burn. Matching serial numbers on everything but the PCB, so that's been swapped out at some time also.
Rather than plug it in and see what happens, like I would've done years ago, I uplugged the power to the monitor, and the two edge connectors, and tested the voltages at the AR2 after having a good look over.
Everything checked out as would be expected, with the unregulated voltages being higher and the 5v at the + side of C1 being almost spot on. Voltage to the monitor is 50v-0v-50v. I even go to the edge connector and checked at those pins, all good.
Next I cleaned the edge connector fingers with a fiberglass pencil, and then the various connectors on the AR2 get the Deoxit treatment, check everything again, all good.
So I plug the pcb back in, place my DMM probes in the 5v and GND test lugs on the PCB and hit the power switch, 7V! WTH!
I turned it off right away, but what the heck? How am I getting 7v on the board, whenever I just verified 5v from the AR2.
