ET-3404 6809P adapter clone bare PCBOARD for Heathkit ET-3400 Trainer

Description

This BARE PCBOARD can be used to build a clone of the ET-3404 6809P adapter for the Heathkit ET-3400/ET-3400A trainer. The ET-3404 adapter board is used to replace the trainer's onboard 6800 or 6808 microprocessor and ROM with a 6809P microprocessor and 6809-specific EEPROM. This auction is for the BARE PCBOARD only -- you will need to source any other components necessary to complete the board, as well as program the EEPROM yourself. The commonly available TL866/minipro programmer is sufficient to program the EEPROM. The BOM, schematics, etc., are up on my web page, which is linked to the attached youtube video.
Heathkit ET-3400 Part 3: The ET-3404 6809 adapter, cloned
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The PCBOARD is fairly true to the design of the original. The primary difference is that I modified it to use a modern AT28C64 EEPROM instead of the ROM/EPROM that would have been used back in the 80s. The AT28C64 is easy to program, easy to erase, and available from modern distributors.
NOTE 1: As described in the video, I did encounter a few bad MC6809P microprocessors when building my adapter. The 6809P is a vintage IC, not available from conventional suppliers. As such, I'd consider the 6809P to be one of the harder parts to source correctly. The video does contain some hints on how to detect a faulty 6809P. Do make sure to buy a 6809P and not a 6809 or 6809E. Only the "P" variant includes the built-in clock generator.
NOTE 2: The board can be used a drop-in replacement in the ET-3400-A (newer model), but the older model ET-3400 trainers require the clock generator IC be replaced with a "clock adapter". This makes installation in the early ET-3400 a bit more work than the ET-3400-A. Please do take a visit to the ET-3400 users group where you can download the instructions for the original ET-3404, and it'll explain how to make the clock adapter.
NOTE 3: The 6809 is binary-incompatible with the earlier 6800/6808 microprocessors. Building one of these adapters will let you do the 6809 experiments, but if you want to go back and perform 6800/6808 experiments, or use an ETA-3400 memory/IO expansion, then you'll need to restore your trainer back to the original state.
NOTE 4: I'm the only one who has built this particular clone to date.
You should consider this project to be in alpha state, possibly requiring some diagnostic effort if it doesn't immediately work for you.