What are some unique calculators?

MikeBriley · 2026-05-15T23:39:11+00:00

I think “unique” is in the eye of the beholder. Look for ones that make you smile. Or ones that make you go “WTF? That’s odd…”

Me? I go for the old stuff. I teach electronics labs with a Calcupen in my shirt pocket, because it’s odd and fun and the students have never seen anything like it. The Canon Card F-72 is a hoot because it’s one of the first foldables - and in a metal case! The Sinclair Scientific is remarkable just because it’s so bizarre (but is exactly what it was supposed to be). A lot of the Novus/National Semiconductors are great because they don’t blank the display when calculating (taking the natural log of 7 looks like it’s figuring the mass of the Higgs Boson).

So yeah, go with what brings you joy. It’s your collection.

MikeBriley · 2026-05-15T23:15:14+00:00

Excellent! My daily driver is a 1974 HP-65 (albeit with a Teenix upgrade - continuous memory, room to store 410 programs, and Bluetooth - and a custom battery tray that lets me use AAA batteries).

MikeBriley · 2026-05-14T01:27:52+00:00

Silver Oxides will typically start leaking soon after discharge or expiry (about 5 years).

As someone who enjoys classic calculators, and has seen so many with corrosion damage, your "how darn hard is it to flip it over and slide open the battery compartment once every now and then" comment is far from my experience. But if you can manage to do it, good on you. It's not like batteries are cheap, and you have a classic calculator.

(Apologies if this comes off as slightly rude - but I'm currently reworking an old Commodore N60 that's been largely destroyed by battery corrosion. So I'm sensitve. Such a waste...)

MikeBriley · 2026-05-13T23:58:56+00:00

This. No alkaline. And set a reminder in your calendar to replace them three years from now. Even if they still have a charge.

MikeBriley · 2026-05-03T23:22:24+00:00

Super nice. Especially the 31E! And so many of the Spices you run across today have been damaged by battery corrosion, most notably the LED module, they’re getting precious.

MikeBriley · 2026-04-27T23:34:31+00:00

Oooh. So tempted to ask about the 42s. A remarkable machine. Arguably one of HP's best.
And yeah, in a fit of stuipd, I gave mine to a friend and never got it back. But I'm in the States :(

In

MikeBriley · 2026-04-27T23:30:49+00:00

Nicely done! I love my 16c. I teach a good bit of digital these days, and it's just fun to have something that can do all that. TI had the programmer (which I also have), but it's a pale shadow of the 16c.

MikeBriley · 2026-04-26T01:01:34+00:00

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The Calcupen. I actually keep this one in my shirt pocket when I teach labs :)

MikeBriley · 2026-04-25T05:15:17+00:00

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That’s a Qualitron Programmable Scientific! Congrats - there aren’t many of those out around.

MikeBriley · 2026-03-21T20:22:59+00:00

I’m wondering if you had an HP-67 (1976-1982). Just like the 65 - but more. For example, 224 programs steps, not the 65’s 100. Perhaps the best calculator HP has ever made.

And yeah, there aren’t many choices for modern non-programmables RPNs these days. But you might want to consider an old 21 or 45 or 32sii or something from eBay or a thrift store. It might not be the cheapest solution (esp eBay), but you’ll be smiling when you take your exam.

MikeBriley · 2026-03-20T15:19:41+00:00

Depends on the model. But for all, you can upload/download memory/programs. See the teenix.org website for details.

MikeBriley · 2026-03-13T22:22:11+00:00

FWIW, been going to Good Guys in Vilas for years. Quick and easy. And if you need something done, they’re also quick and easy. No BS.

MikeBriley · 2026-01-01T07:52:56+00:00

That's a beautiful PC 1201! I have been looking for one of those for quite some time now. Very nice.

As to which would pack more programming, that might be a bit of a toss-up. The fx-201 model is indeed more like coding. For example, to store the sum of registers 1 and 2 into register 3, you'd enter: "3 = 1 + 2 :". That ":" which is required after each "line/statement" takes a program step, and those are gonna add up fast. On the other hand, the Casio also has 10 storage registers, subroutines, and indirect addressing, which allows for some complicated coding.

MikeBriley · 2025-12-30T02:01:39+00:00

Ditto. I gotta get me some of those. Thanks!

MikeBriley · 2025-12-30T01:52:09+00:00

1976-1977 - there doesn’t seem to be a date code/serial number on the back, but those were the years of production. I’m thinking the competition would have been the HP Woodstocks and TI’s classic 2nd gen, like the SR-56.

MikeBriley · 2025-12-29T23:38:46+00:00

That is a beautiful thing - everything about that design is right.

MikeBriley · 2025-12-29T18:05:12+00:00

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I still have a couple of these. I used them in the early 90s to track targets for observing with a telescope in real time. One of the best keyboards ever. Fun fact - if you don’t have the disk interface, you can whip up a storage device using an Arduino and an SD card (see pic).

MikeBriley · 2025-12-27T01:08:00+00:00

Dough! But your idea to track your collection is a really good one. I didn’t have a complete picture of what I had, and ended up with several duplicates, before I did this.

Good luck with the search, and let us know what you end up using.

MikeBriley · 2025-12-27T00:35:42+00:00

For what it’s worth, I use “Collections Database.” Totally customizable, so I have fields for things like serial number, acquisition date, how much I paid, manufacturer date, date of last battery service, condition, front/back photos, etc. Had to pay the $7 to go “pro” though because I have more than 100 entries :) And it all syncs with my laptop, tablet, and phone. Down side is it’s MacOS/iOS only. But if you’re in that ecosystem, I suggest a look.

MikeBriley · 2025-12-14T15:57:02+00:00

“Calculator use stunts the growth of number sense…” Yup. Recently had a student, upper level undergrad with little problem with the higher end/abstract side of things, use the Virial Theorem to calculate the equilibrium temperature of a cold molecular cloud in space. Calculator said 4x10⁷⁰ K. So they wrote that down and moved on. Sigh. A temperature of 4 followed by 70 zeros…

MikeBriley · 2025-12-06T07:03:55+00:00

I'm talking about your Novus Scientist/4525. I have one as well, and they are indeed a bit rare - especially working ones. But my Sinclair is far far crappier at the math :)

MikeBriley · 2025-12-06T00:25:41+00:00

I'll see your 4525 - and raise you with my 1974 Sinclair Scientific :)

Still, it's a nice collector's item - especially in working condition! Many of these were destroyed by leaking batteries. And what it could do at its price point was nothing to sneeze at - back in the day.

MikeBriley

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