Don't you just hate it when you're making a "calculator check" and a machine that worked perfectly the last time you tried it suddenly doesn't?
One of my two HP-67s has decided that it will not longer run on batteries. Runs fine from the AC adapter, but of course the card reader requires battery current to work.
I seem to recall reading of this syndrome in the past and that the fix was rather simple, but I can't find it now. If Katie or someone else hardware-knowledgeable would remind me, I'd appreciate it.