HP-11C Self-Test Help

[lemontea]

Your calculator is probably working fine.

If it passed the ON and X test (multiplication key), then it is likely working.

The ON and + test is just the same test but runs indefinitely.

The ON and DIVISION SYMBOL test, which you are using to test the keyboard, must be performed by pressing the keys in order from LEFT to RIGHT and then TOP to BOTTOM. The sequence is crucial.

If the keyboard test is working properly, "different segments in the display area are lit" (quote from the Owner's Handbook, page 236). The ENTER key is pressed twice in this sequence.

If you press a key out of sequence, "Error 9" is displayed.

Otherwise, when everything is fine, "11" is displayed when you have pressed the last key.

ALTERNATIVELY you can just press keys normally when doing calculations to see if they work.

My guess is your 11c is fine.

I have two of them! They are great!