Hello guys,
I just found this forum by coincidence while looking for potential fixes for my Texas Instruments TI-89 calculator.
The issue I am having is that I didn't use the calculator for several years. Luckily, I didn't leave the main batteries in the compartment.
However, when I tried to put new batteries and turn it on again, the screen is very dim.
What I mean is that the calculator actually turns on, but I need to look from a specific angle to see anything, and then, if I open any of the F menus, then almost the whole image is lost.
I already checked the usual problems for these calculators, like the rusty contact pads or the ribbon cables.
One curiosity is that if I remove all batteries, and then put them back, and switch it on, for a second, the contrast of the screen is normal, but then it dims, and is the same as before.
Have you ever seen such behaviour before? If so, can you think of a way to solve the problem?
Thanks!

S.
Did you try adjusting the contrast?
Yeah you can try pressing the green diamond and then + a few times to see if it's the contrast (iirc).
tr1p1ea wrote:
Yeah you can try pressing the green diamond and then + a few times to see if it's the contrast (iirc).

Yes, I obviously adjusted the contrast before, that was my first bet.
However, no matter if I increase or reduce the contrast, the best I can get is around the middle. From there, it dims the screen, either increasing or decreasing the contrast.
I already dissassembled the calculator and didn't see anything obvious...
OK no worries - sorry if it sounded patronizing, just that you would be surprised how often people encounter this issue and the contrast is the problem (or flat batteries etc) Smile.

What sucks is that it means it is a more sinister problem Sad.
tr1p1ea wrote:
OK no worries - sorry if it sounded patronizing, just that you would be surprised how often people encounter this issue and the contrast is the problem (or flat batteries etc) Smile.

What sucks is that it means it is a more sinister problem Sad.


No problem... I would probably have done the same. I already did an extensive research online, and was surprise how many people didn't know something as basic as adjusting screen contrast...
Anyway, the behaviour I have seen is certainly odd, cause it doesn't have the typical missing lines or half black screen... It is a shame that a perfectly working calculator cannot be used because of screen glitching... Sad
I wish I knew more about the ti-89's internals and could be of more assistance to you. I have a ti-89 titanium, but that is completely different inside
  
Register to Join the Conversation
Have your own thoughts to add to this or any other topic? Want to ask a question, offer a suggestion, share your own programs and projects, upload a file to the file archives, get help with calculator and computer programming, or simply chat with like-minded coders and tech and calculator enthusiasts via the site-wide AJAX SAX widget? Registration for a free Cemetech account only takes a minute.

» Go to Registration page
Page 1 of 1
» All times are UTC - 5 Hours
 
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

 

Advertisement