Service required for HP 9160A Optical Card Reader

[TASP]

As always, wait for a consensus before doing anything, however, I've seen fuses blow from apparently not much more than old age, and I'm thinking your fuse in the 9100B was ancient indeed.

Maybe there isn't anything wrong with the card reader ??

As in human medicine, the first rule is to do no harm. Maybe ohm out the optical card reader and see if it measures anything other than a dead short, then reporting back here for the rest to weigh in.

If it does measure a dead short, that is significant, and potentially easy to find.