|Re: HP 34C|
Message #2 Posted by Vieira, Luiz C. (Brazil) on 28 Sept 2009, 10:52 a.m.,
in response to message #1 by Howard Jones
I had an HP38C with that kind of behavior. In that case, it was a bad power supply unit. I had it replaced and it worked fine since. Unfortunately I had no time to go ahead and find the actual cause: bad contact, faulty component, etc. All I can tell you is that I replaced it and the HP38C worked fine since.
There is also a possibility of your unit being a solderless one. In this case, a bad contact in the RAM terminals would be enough causing it to be erased due to power loss. Best chance would be opening it, disassembling and cleaning contacts. It would also be a good idea to check if the IC´s terminals can be a little bit bent against the flex circuit, so contacts would enhance.
Chances are that you could have a simple bad contact in the batteries, but since you have the same problem even when it is on the charger, I´d consider the power supply unit, instead.
Not too much of help, though...