Got an old TI-84 from a friend. Doesn’t turn on, and tried everything TI suggested. Solution? The power of Youtube, and crappy soldering.

It was a fairly simple fix: the battery wires wore away at the pads, deteriorating the electrical connection. So, I dropped a glob of solder on each battery pad, hoped for the best, and placed the cover back on.

Note the solder mask poking through where the batteries are supposed to connect.
Note the solder mask poking through where the batteries are supposed to connect.

For cleaning purposes, I opened up the keyboard and pulled out all of the keys. The previous owner was fairly enthusiastic about scribbling on the case with a ballpoint pen, so I tried several solutions (alcohol wipes, diluted Simple Green, concentrated Simple Green, 70% rubbing alcohol, baking soda) before finding success with a sponge and detergent.

To be honest, now that I’ve seen the calculator’s insides, I’m now even more convinced that TI is scalping high school and college students due to their high profit margins. Sure, they were probably revolutionary when they came out more than a decade ago, but with a computer in every pocket, it’s difficult to justify the $100 price tag on each calculator. The Washington Post has evidence to back me up: with a virtual monopoly on the educational market despite inferior hardware, it’s no wonder TI can continue to charge exorbitantly.