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HP-21 malfunction
11-14-2019, 02:40 PM (This post was last modified: 11-14-2019 02:41 PM by Moggul.)
Post: #1
HP-21 malfunction
I recently acquired an HP-21 and am trying to resurrect it.

The battery pack was in very bad shape so when connected to the charger the display was erratic, showing a flickering 0 in the rightmost digit. After installing fresh rechargeable batteries the display showed a single strong 0, and now it shows all 0s without any flickering (see pic sequence). This is both when connected to the charger and when powered by the batteries alone.

               

Is the calculator resurrectable or should I go the Panamatik route?

Thanks!!!


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11-14-2019, 03:10 PM
Post: #2
RE: HP-21 malfunction
This is almost certainly a dead ACT. A PANAMATIK kit is the best solution.
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11-14-2019, 03:49 PM
Post: #3
RE: HP-21 malfunction
Connecting the charger with a bad battery pack (or no batter pack installed) is one of the quickest way to damage one of the HP-2X (Woodstock) or HP-3X (Spice) series calculators. Many collectors charge the batteries externally (or use non-rechargeable batteries) just to be on the safe side.
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11-15-2019, 12:09 PM
Post: #4
RE: HP-21 malfunction
Hi,
PM sent.

Ignazio
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RPN...What else!
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