HP-67 1706A00901 [RA and RB with Spike, doesn't read - doesn't write]

[albertofenini]

Hi Andi

I hadn't because all the other, or at least three (I haven't finished to troubleshoot the one
with serial XXXXA01234) have shown problems at the CPU board level but it was worth a
try, so I did it and :

XXXXA00901 chassis and card reader with CPU XXXXS02334 didn't work
XXXXA00901 chassis and card reader with CPU XXXXA01636 didn't work
XXXXA00901 chassis and card reader with CPU XXXXA01234 didn't work

I can try to de-solder the CRC chips and check if underneath there is some
corrosion, may be is a cold joint not working anymore

I also have a spare HP67 board with some ROM0 problems but maybe that CRC
is working so I'll keep up with the tests

Thanks for the support, take care

(11-21-2021 05:27 PM)AndiGer Wrote:  

(11-21-2021 03:06 PM)albertofenini Wrote:  This happens only with this CPU board.

Did you test the card reader together with a board of the currently non-functional 67's?
If there aren't the spikes you could at least combine two machines to one functional? ?