The stripping:

First step was to remove all the ICs, and electrolytics, the regulator, the seven segment displays, and all the IC sockets and jumpers to prepare for cleaning.

Sockets were carefully removed using conventional solder sucker and copper braid to clear all the holes being very careful of the heat setting on the soldering iron and using just enough heat to get the job done.

Note the severe heat damage from the old 7805 regulator heat sink.

Cleaning:

Next I removed all the electrolytics, a broken  resistor, the LED and the seven segment  displays. Initial cleaning was done with a horse-hair brush and then MG Chemicals Flux remover. All holes and pads were cleaned up with a flux infused copper braid (Super wick) using as little heat in the soldering iron as I could get away with.

Assembly and smoke test:

Next installation of gold-plated needle-pin headers to replace the cheap sockets was completed and the regulator was replaced with a pin-compatible switch mode regulator, an OKI-78SR-5/1.5 that is available from Mouser and other sources. This regulator does not require any heat sink and out-performs the original 7805 shown in the second photo for comparison.

All the key switches worked but are, understandably, noisy. There is no source for these so I left these as is. In order to ease program entry because of these inherently noisy switches, I will add a modification later. I really hate getting 50 bytes into entering a program only to discover the last entry was incorrect and having to restart the entry from 0x0000 again!

Both displays were bad: one had a single dim segment and the other a completely dead segment. New ones (actually used removed from other equipment) were source through EBay.

The missing 2101 RAM ICs were populated with 9101 RAMs sources from EBay and jumpers were installed to configure the board as a stand-alone. Note that all the jumper pads now have needle-pin headers installed to facilitate jumper changes easily.

All the ICs were installed in their appropriate sockets and the board was connected to an 8V supply for initial testing.

Initial Testing:

Initial power-up revealed that the keyboard was not functioning. Further troubleshooting revealed that IC A15 (74LS00) had failed. This is the main clock oscillator that drives the 1802. No clock = no DMA to read the keyboard!

The 74LS00 was replaced with a 74HC00 and clock was restored.

A quick test program was keyed in (the classic Q <> input key test) was successful!

0x0000    7a

0x0001    3f  01

0x0003    7b

0x0004    30  00

Modifications:

Color coded binding posts were added and cables made for composite video, cassette recorder, and power.

A TI-311 based display was added and this was tapped into the Hex keypad buffer on the input side of the CD4016 switches. This will allow display of anything typed into the keypad BEFORE hitting the input key and eliminate noisy input entries.

Additional Testing:

The pixie chip was tested by entering in the classic Star Trek display program. The composite display is a cheap vehicle backup camera display from Amazon.