71B battery problem


So my 71B, which has been working faithfully for the last three years (on the same batteries!) recently had it's batteries 'liberated' when no other AAA's could be found around the house. A month later I replace them (with bog-standard alkaline AAA's from Ikea) and it's not happy.

The display has every element turned on, and it won't respond to any key presses. Anyone know what's wrong with it, or what I can do?


Try take the batteries out and connect the battery contacts to each other with a metal wire. You may have some kind of static build up.


Just tried that - alas it's still the same.



    Did you try pressing the [ON] key and the [/] (divide) key
    simultaneously, holding for a couple of seconds, then
    releasing ?

    The manual suggests this:

    • Unplug all modules and peripherals

    • Remove batteries

    • Press the [ON] key for 30 seconds

    • Insert new batteries (correct voltage and polarity, etc)

    • Press [ON] and [/] simultaneously for a couple of seconds

    This should completely reset the machine. If this doesn't work, I would let it without batteries for 24 hours then try again.

    Hope that helps.

Best regards from V.


Success! The reset worked. Thanks all!

I should probably get a manual for it...


Also, since every element is turned on, double-check that the contrast is not out of whack. Good luck!

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