Repaired the switch defect, now enjoying the PiDP10

FOUND A SHORT BETWEEN ADJACENT DIODES ON THE SWITCH MATRIX

It was not obvious at all looking through the stereo microscope, but a continuity tester verified that it was indeed a short between two very close leads on the PCB. I resolved the issue, tested the switches and now it works just fine.

APPLYING ONE HACK TO THE KIT

The kit came with holes to place a keyswitch and a USC C female power socket on the back panel and solder points on the main PCB. This allows me to plug the USB supply in the rear and use the keyswitch to power on the Raspberry Pi.

POWER OFF STILL REQUIRES CARE, NOT JUST THE KEYSWITCH

The DEC software needs to shut down in an orderly manner to protect the integrity of its filesystems. This is done for ITS by issuing the 5down command, which shuts down in five minutes. Wish it was quicker but that is a possible hack for the future. Then, the Linux system on the Raspberry Pi has to be shut down in order to protect the integrity of the Linux file systems, using shutdown now in a terminal window. Once that completes, the power switch can be turned off. 

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