Jobs to do:

  1. Do a hi-res scan of both sides of the PCBs - Done
  2. Update a copy of the Kicad schematic used for the recreation project - Doing
  3. Import components to Kicad PCB place and then spend many hours tracing the tracks from the scan - Not Doing yet
  4. After DRC checks create Gerbers for PCB manufacture - after step 3
  5. Start populating the original board. - after step 4
  6. When we get the PCBs back build one and then take over the world. 

1. Scans

This wasn't too hard. Had to do some stitching but came out alright.

2. Update Kicad schematics

My recreation uses SRAM instead of DRAM and replaces the two EPROMs with a single FLASH so need to change these so we can layout the board. There is also a PROM ( 6331-1) that is used for the Colour Look Up Table (CLUT). These are hard to come by so I'm looking at using a ATF22v10 which as a different pinout and pin count. So not sure what to do here. Keep the board the same and make an adaptor or commit sacrilege and change the board design??!! Any feedback welcome here. Same problem with the audio out. The output is just a BC548 which gets awfully hot. The user group newsletters has as a fix by using a bigger transistor and a 1w resistor. Same dilemma but in the case our ancient forefathers fixed this, so is it cannon to redesign the board, or bodge it after?

3. Import Components

 This is just importing the components onto the board. The components will be laid out then manually tracing the tracks, using the scanned board as a guide. Haven't done this before but should be too hard. I hope 😉

4. DRC Checks

Yes do the usual Design Rules Checks. This is a big board and don't want to find out after they are manufactured that there is something wrong!

5. Populate the original board

As the title says, start on the real board. I have all the components so should be good. The original used 74LS and NMOS ICs. I only have  CMOS versions the Z80, 8523, MC6845 etc... so will have to use 74HCT me thinks. See how we go but hopefully the board will work straight out of the box. Will be using the original ROM images.

Keyboard may be an issue as the key footprint is not your standard footprint. But have already made some keyboard PCBs with the Cherry MX footprint. Need to research that one a bit more.

6. Populate the new board

As above, I hope. Then use it to play a game of Thermal Nuclear War. What could go wrong?