I want to start out my story by stating that I know, from reading the various postings on this forum, and from reading the HP literature, that the 82106A memory modules from a 41C do not work in the 41CV. It already has 320 registers (00-319) of memory, etc.
However, today I had an unusual problem with my 41CV. It suddenly went from having 320 registers to having only 192; and it lost several programs in the process. It also exhibited other weird behavior (showing all "@" signs across its display, ON switch becoming non-functional, USER toggle stuck "ON", etc. etc.) which resulted in me doing several complete resets, losing all my programs, and eventually removing the back from the calculator. I cleaned all the contacts, etc. which I could get to, but could find nothing visibly wrong (it was, in fact, already one of the cleanest calculators I have ever opened). However, it still only had 192 registers of memory upon reassembly.
On a hunch, or in the interest of stupid experimentation, I inserted two 82106A memory modules into ports 1 and 3 of the calculator. It immediately began showing 320 memory registers. If I remove the 821067A modules, the calculator will retain 320 memory registers until either A) the power is shut off, or B) the SIZE command is used, whereupon it reverts to 192 memory registers. Reinserting the two 82106A modules will re-establish 320 memory registers.
Does anyone have a logical (or even illogical) explanation for this bizarre behavior? Thanks.
Take care.
Wayne.