Texas Instruments
I never personally owned or even used any TI calculators. But I well remember the TI vs HP wars of the '70s. HP would innovate and TI would replicate and add an extra couple features. HPs felt more solid and bore a stamp of quality, but TIs had more bang for the buck. And of course, HP used that crazy RPN convention with its geek-appeal while TI had an equals key which made more sense to many. In my math/science circles, arguments broke out over who had the better calculator!
TI SR-50
A response to the HP-35. Look how the color scheme echoes the HP-35 except for the orange "=" key that screams "you don't need to live with RPN!"
This unit works perfectly.
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I run this and my other "Classic" TI calculators with battery packs I've modified to use any AA batteries. Click the photo for details
TI SR-50A
Not long after the release of the SR-51, below, TI restyled both it and the SR50, above, without changing the functionality.
I have to say that the new designs make more sense. There was no real reason for the original's silver top section to encase the first row of keys as if they were somehow special. Plus, that silver coating wore away pretty fast, whereas in the redesign it's a durable metallic label.
But while it's logically an improvement I don't think it's as attractive.
TI SR-51
A response to the HP-45. Again, they copied the color scheme, and again they improved upon the feature set so as to be more than a knock-off.
This is a very rare 1st version of the SR-51 that was only produced for a couple months. It's in near mint condition, the only blemish being some missing paint below the power switch (which might even be a manufacturing defect.) It works perfectly.
TI SR-51A
The restyled version of the SR-51, above.
Ditto my comments for the SR-50A, above the SR-51.
TI-30
One of the most popular calculators. Note how the oddly-shaped box boasts: "with algebraic operating system" (translation: we don't make you use RPN.)
This unit is in great condition and works fine.
TI-1200
A very popular 4-banger.
This unit works and is in great condition.
TI-1250
Add a memory to the 1200 and get the 1250.
TI-1766
Their first solar calculator. Note the wording "solar and light powered". TI soon realized the redundancy and changed it to "light powered" for their future calculators.
Also note the lack of any on/off provision. It's just on when there's light and off when there's not.
TI-1780
This is an early solar powered, credit-card-sized calculator. Stylishly designed in an aluminum case, it's durable and slips into a pocket.
TI-30Xa
My kids used these in high school. That they still work testifies to their durability!
TI BA-35 Business Analyst
A pretty solid calculator, well protected by a clip-on cover.
TI SR-10
Brought to market in late 1972, this was arguably the first "scientific" calculator in that it displays numbers in scientific notation. However it lacks much in the way of mathematical power - no logs, trig functions, powers/roots other than 2, etc.
This is a Version 1, having the SR10 designation in the black plastic frame below the display. (Version 2 and later displayed it above the 1/x key in the gray frame around the keys.)
It's in excellent condition and works well. I also have the manual for it, and a blemished case.
Of special note, while this calculator used rechargeable NiCads, they were neither hardwired nor in a removable battery pack as with most other calculators. Instead, simply removing 2 screws and taking the back off reveals a compartment for 3 AA batteries. You can install NiCads for rechargeability, or standard alkalines. But be aware that the AC supply will not power the calculator unless NiCads are installed! (Don't try to use AC w/ alkalines.)
TI-2550
What a bold look! It's a big wedge, it has big keys and saturated colors. I love it.
TI 36 Solar
A stylish and powerful light-powered calculator. Note the oxymoronic "Anylite Solar" in the lower right corner!
Just look at all the functions on this baby. Note that they could have fit 3 more functions above the log, ln and y-to-the-x keys... I guess they ran out of ideas!
TI 35 Slimline
Another stylish wallet-sized scientific calculator. Quite nice and a little simpler than the 36, above.
TI LCD Programmer
If you were a bit-twiddler, maybe you would have needed one of these to simulate your binary and hex arithmetic and register operations.
It's a nice looking calculator, but has a terrible keyboard.
TI 60
Another slim wedge. This one is programmable, though it lacks conditional logic. But it does have permanent memory.
TI BA-54
Another of TI's slim wedge designs with a poor keyboard. This is programmable for the business user.
TI 82
A nice graphing calculator. It has a really good feel and nice, clean appearance.
It has a good hard cover that slides on and off.
TI 59 and PC 100A Printer
Here's something I can authoritatively tell you as a programmer for 35 years: you can't do it without paper. I laugh when I hear people talk about a paperless society.
Anyway, the TI 59 is notable for being the first calculator to use replaceable ROM program libraries. Little modules of up to 5000 steps-worth of programs could be plugged into the back to adapt the calculator to a variety of business and science specialties. With the additional ability to create new programs and store them on magnetic cards, it's a capable machine.
The PC 100A printer can be driven by a program to output alphanumeric text as desired. It can also be used to "echo" everything displayed on the calculator.
TI-1031
Nothing special. Just a wallet sized 4-banger from 1981.
Note that it uses button batteries. Most calculators this size became solar powered before too long.
TI-5025 Printing Calculator
This was TI's first shot at a handheld printing calculator, and it is none too shabby. A bit hefty maybe, with 7 sealed NiCads, and the printer is a tad slow, but if you needed an audit trail this was not a bad way to get it.
If anybody knows how to replace the NiCads in this machine please let me know! They're in a compartment of the case that seems impossible to open without destroying something!
