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Recharging batteries in a HP75 Pod - Printable Version

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Recharging batteries in a HP75 Pod - GE - 08-16-2006

Hello, I have a battery pack of unknown condition which came with my HP75+Pod.

I wonder if there might be a problem if I try to recharge it inside the dedicated slot in the Pod without knowing if the pack is good.

Can I try this or do I have to ensure the pack is good first ? I have only a multimeter at hand at the moment and no suitable external charger.

Thanks for sharing your wisdom.

Re: Recharging batteries in a HP75 Pod - David Smith - 08-16-2006

If you have an original HP pack, it is over 15 years old and is bad. Attempting to charge it should not cause any damage though.

Re: Recharging batteries in a HP75 Pod - GE - 08-16-2006

Thank you !

A sticker inside the pod's battery door says that to work correctly the machine needs a working pack in place. Do you think I must be sure that the pack works before powering the machine on ?

I guess this just means that you must have a good pack in place if you run the machine off mains power.

Can I put the pack into my HP55 to test its status ?

Thanks again.

Re: Recharging batteries in a HP75 Pod - Vieira, Luiz C. (Brazil) - 08-16-2006


I have a battery pack for the HP55 that I have already used in an HP75D. For as long as I can think of it, there is no issue using a battery pack in one of them that had been used (or charged) in the other.

In time: the HP55 original charger is able to both 1) supply the internal circuits of the calculator with regulated voltage and 2) charge the the batteries with a proper voltage value, at the same time. This is why it uses a connector with three connecting points. If you suspect the battery pack is bad and you decide to use it in the HP55 with the charger in order to test it, the deffective pack will not be charged and chances are that the calculator works fine, anyway. I'd try to test the battery pack outside the calculator; I do not think it´s worth risking an HP55 for testing purposes.


Luiz (Brazil)