TDS 512k RAM CARD acting up


I have resurected my HP 48GX. Haven't used it for a few years. Of course when selected on I got the 'Warning' about the invalid card.

I ran the PINIT command and then followed the TDS web site discussion on setting the alarm to charge the card. I then archived my programs. For the next few days all was well, until...

After leaving the calculator off for a few days (having charged the memory card) the Warning returned and of course the archive in port 2 disappeared. I did a few charge cycles to see if I could reset a bad NiCad memory cycle but to no avail. The card will not hold a charge and therefore the memory for more than a few days.

The card battery is obviously losing it's charge, and I suspect the internal rechargable battery is the cause, either due to a poor 'memory' or bad battery.

Has anyone open one of these up and replaced the NiCad cell? Or am I missing something?

Cheers, Geoff

After following the

Edited: 12 Mar 2009, 8:17 a.m.

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