HP-67 not behaving?

[markhen]

Tony - thank you so much for recreating! It does indeed seem like part of the RAM has failed (for example where the display format is stored, and program steps?). I am experienced with the iron and static prevention, I’ll try not to mess up the rear label and crack this baby open to investigate! Due to travel this probably won’t be until later this week. I will report back!

Cheers

Mark