HP11C Calculator

[Cristall11C]

My HP 11C did not turn on anymore (it had just two hours before, I do not remind having seen the low batteries asterisk), so I changed the batteries. Since I have put in the new batteries it keeps blinking the last Digits that were on the Screen, before it had turned itself of. Ican press any combination of keys: no change, removing and putting in the new batteries: blinking starts again. What can I do?

[BartdB · Accepted solution]

Hi,

These calculators sometimes get stuck in erratic behaviour.

You can try:

1) Reset: With power off, hold down ON. Press and hold subtract key. Release ON. Release subtract key. It should say "Pr Error."

2) Remove the batteries for at least 12 hours.

3) Remove the batteries and short the calculator battery contacts for a few seconds with a paperclip or similar conductor.

Please ensure you have a good brand of batteries of LR44 or SR44 type.

(Note: NEVER put the batteries in backwards or put anything other than the suggested batteries in the calculator).

To verify operation:

Self Test: With power off, hold down ON. Press and hold multiply key. Release ON. Release multiply key. It should display "running" for a about 25s, then display -8,8,8,8,8,8,8,8,8,8, and all indicators. If it says "Error 9" there is a problem.

Self Test with keyboard test: With power off, hold down ON. Press and hold divide key. Release ON. Release divide key. Then starting at the top row, press all keys left to right, pressing Enter once in both 3rd and 4th row. The display changes with every key press. At the end it should display "11". If it says "Error 9" there is a problem or the keys were pressed in the wrong sequence.

Hope this helps.

[Cristall11C]

I removed the batteries for a few hours and inserted them again, it worked!

Self tests are OK!

Thanks a lot