The power supply now runs fine and the MV/3200 starts every time but with a tweak; since the battery in the timekeeping circuit MK48T02B-12 is flat, every power on test stops at the character “D”. Since the MK48T02B, in addition to being an ultra low power SRAM and a real-time clock, it also is the power-fail control circuit which fails on power up. In order to power up, power must be applied, the date and time set and then leave the system on for a few minutes. Rapidly power off and then on makes the power on tests pass.
I have ordered and received a new MK48T02B-12 but I am waiting for a de-soldering gun that I have ordered to arrive before replacing the chip.