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Need power requirements for an HP 67 calculator

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  1. 19th February 2004 05:48 PM #1
    Brocktune
    Brocktune is offline

    Default Need power requirements for an HP 67 calculator

    Found an old calculator and I want to power it up--the batteries are dead and no charger.

    Anybody know what V/A the power input is looking for?
  2. 19th February 2004 06:25 PM #2
    Sebi
    Sebi is offline
    How many cells the battery and what type?
  3. 19th February 2004 07:29 PM #3
    Brocktune
    Brocktune is offline
    Three batteries in the battery pack. I read somewhere that they are 3.75V, but I don't know if they are in series or parallel.

    I just hooked it up to a power supply and gave it 5V. It turned on and seemed to work okay, so I guess 5V is okay. That also must mean that the three batteries are in series. A low voltage light came on if I lowerd the power to 4V.
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