Want turn on when I change batteries - Texas Instruments TI-84 Plus Calculator

To change the time on a Tracfone LG440G, turn the phone "off", then turn it back "on". If that doesn't work, turn it "off", remove the battery, reinstall the battery, turn it "on". Time should display properly. No way to change the time manually.

The backup battery is only to retain the contents of memory while you change the main batteries. It does not affect the operation of the calculator in any other way.

TI calculators have an annoying habit of dimming the screen when the batteries are changed so that it appears as if the calculator isn't turning on. Turn the calculator on (or at least press the ON key). Press and release the 2ND key. Press and hold the Up-arrow key for a few seconds and see whether the screen becomes legible.

If this doesn't do it, please reply to this post and we can go on from there.

Most cameras don't operate well with ordinary batteries. They need batteries like alkaline, ni-cad, rechargeables, etc.

You say you changed the batteries. Did you also change the back up battery? It's located in a little door with a screw right above the AAA batteries.

My students have come to me many times and have said that their calculator will not turn on. Most times it is that the contrast on the screen has been turned down and the calculator is turning on but the screen is too dim to see that it's on.

To check your contrast, turn the calculator on, press the 2nd key and the up arrow. This is how you darken the screen. You lighten the screen the same way but you use the down arrow instead.

Charge fully the batteries you have, to prevents the camera distinguish the type of batteries (maybe the camera senses the charge), turn on the camera and you will have access to the menu to set up the batteries type correctly, that´s all.

was it ever left in the sun?

Your motherboard backup battery is gone.
This is a watch type battery mounted on the motherboard that powers the chip (CMOS) that retains basic information (BIOS) about your computer while it is turned off.
The battery is gone and not holding the time and date.
The battery is very easy to change, do you have a tower computer or a laptop and are you OK with looking inside the case for the battery?

I had a smiler problem with Alkali batteries. Thereafter I started using rechargeable batteries and also changed the setting to Ni-MH. Its working fine now.

You need to power it with rechargable batteries. with the MAH being no less than 2000. I bought a charger which came with 2batteries for less than a tenner

My problem is this; i changed the battery after i had signal that battery should be changed. I changed the batteries with new one but when i press the on/off button, the camera will turn on.

I put in new batteries again and is still the same problem.