Ti89 responds to resets but nothing else
If the calculator is several years old it may be showing its age.
There is a connection point between the keyboard and the display
that over time loses its efficiency. Try this: press a number key
and at the same time apply pressure with your thumb or index
finger to the region of the calculator just below the display.
If you press hard, the number may just show up in the display.
This is a test for the tightness (or electrical efficiency) of the
Another way to make this test is to twist the calculator while
you depress a number key.
Sometimes the effect is such that the keys on one side or the
other work, or don't work, and the keys in the middle don't work
or work okay. By twisting (don't break it!) the calculator body
while you press the keys will show the weakness of the
connector between the display and the keyboard.
This can be repaired by a good electronic technician if you
explain to him what I just told you.
Aug 29, 2011 |
Texas Instruments TI-89 Calculator