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Progress on Imsai 8080

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  by Bill Degnan - 01/31/2010 18:02
Progress with the IMSAI 8080 that I have with the Thinkertoy Wunderbus backplane.

What was once a box of parts is now a semi-working computer.


Thanks to Mike and Dan for their help.

1. While probing the power supply board Dan sparked a diode, and somehow that woke it up, now functioning. There may have been something touching it.
2. Replaced a 12V Regulator on the backplane board
3. Re-assembled front panel.
4. Put in a new connector for the on-off switch wire from the front panel to the power supply board.
5. Replaced the 8080 processor chip on the CPU card.

Now the system works, but after a few minutes the front panel starts to flicker and is no longer reliably responsive.

Next:
1. Test chips on the front panel board, see if there is a short someplace, etc.

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