HP-67 Diagnostic cards, different versions different behavior

[albertofenini]

Here we go !

HP-67 1612A01116 SD15C
HP-67 1612A01116 SD15A

It actually took a little over 2 minutes, but the SD15C worked out
As you may see I'm running the SD15A from a copy, since the original look to be corrupted

Would I overwrite the original, if I connect the WPS to ground will I be able to write onto write protected cards ?

This unit has a weird behavior, once restored, if used without the outer green bottom shell reads and write 10 times out of 10 times

With the bottom shell this ain't true anymore ...

I have found that, probably because of the de-soldering of the head, the cables push the card reader PCB a little out
of its original place and this, when the bottom shell is tightened, twists the unit hence the unreliable behavior

By putting a small piece of double sided adhesive tape between the card reader pcb and the inner shell we have
somehow fixed this, I'm saying as it may be useful to someone, still it is not reliable as we would like

Also, even if cleaned with a 50% vinegar solution the card reader PCB is not really really clean and I'm not
sure whether what is going to be worst between letting some small spot of oxidation (under the sense amplifier) or
molest it again with another vinegar solution bath, what's your take on this ?

take care and thanks for the support !!!