My personal calculator history

[naddy]

I thought I'd share my personal calculator history.

I probably had contact with simple four-function calculators before, but my first real scientific calculator, back when I was in school in the 1980s, was a Sharp EL-512. My dad used one at work and he also got one at home and one for me. In fact, a couple I inherited are still floating around the house. Objectively this is a fine machine, contemporary to and in competition with the HP-11C, but nowadays I find the keys too small and fiddly.

A bit later I got a Casio fx-7000G. However, the graphing feature didn't prove all that useful and felt more like a toy. Presumably I sold it, I don't even remember.

Around that time, 1987/88, I also encountered my first RPN calculator. I'm pretty sure I had heard of RPN in one of those articles about Forth that computer magazines ran at the time, but it hadn't piqued any interest. My memory is very hazy, I think a classmate had an HP-11C, so I was curious how it worked, played around with it, and immediately liked it. Since I couldn't always hog my friend's calculator, I got one for myself, an HP-15C. This machine carried me through the later years of school and it has continously served me right up to the present.

I also got an HP-28C but the clamshell design was big and clusmy and I never really warmed up to the machine. I must have eventually sold it, ...

... and got an HP-48SX. I warmed up even less to that one. I don't think I even managed to finish reading all the copious documentation I had bought with it. It was too big, but my overriding memory is how slow it was. The user interface was slow and the vaunted equation writer was unusable. Clearly the designers' ambition had exceeded the capabilities of the hardware. I wanted to use it, but in practice the 15C was sufficient and a lot more convenient, so the 48SX landed on the shelf. I intended to eventually get back to it, but the years passed, and when I barely remembered anything about it, I finally sold it off. The buyer was very happy to get one in such excellent condition.

Meanwhile at university the policy was that no programmable calculators were allowed in exams. So I bought a TI-30X, which served in a pinch. I recently found it again in the back of a drawer and was promptly so disgusted by its wobbly rubber keys that I threw it away.

Sometime in the 1990s I also had an HP-16C. Those had already been discontinued, but I think somebody stumbled over an unsold batch in a warehouse and flogged them off? Anyway, this seemed like a nobrainer, since I was doing computer stuff, including bit-fiddling, all the time. Or so I thought. In practice, the 16C ended up in the drawer, and it was hardly worth taking it out. I can't tell why exactly, but I think it came down to the fact that I hardly ever needed to do the calculations it supported. DEC↔HEX, yes, but for that I can use dc(1) without having to take my hands off the computer keyboard. And once you have a hex number, you can do masking and bit operations in your head—I mean, I know the bit representations of all hex nibbles. So, yeah, you guessed it, I eventually sold the 16C, too.

There is a long gap, where I had stopped following calculators. Eventually my 15C developed a small, annoying defect—two segments on the fifth digit are dead—but brief looks at repair reports on the net looked daunting. I might have bought a 15C LE, but I didn't even learn of its existence until years later.

A few months ago, I stumbled over the HP-15C Collector's Edition and immediately bought one. I used the opportunity to read the HP-15C Owner's Handbook for the first time in decades and the Advanced Functions Handbook for the first time ever. I also studied the MoHPC site and many old forum threads to catch up and get a better understanding of the various Hewlett Packard calculators and belatedly learned about the existence of SwissMicros.

I recently picked up a used HP-11C in good condition. That one went downstairs into a drawer, so I can do the odd quick calculation on a familiar machine there and don't have to fiddle with an EL-512. I considered a 15C (CE), but an original 11C was cheaper and good enough.

With my renewed interest in HP calculators, I finally decided to give a Pioneer model a try. The voice of reason convinced me that I couldn't make full of use an HP-42S, and given the ample precedent, after a playthrough of the manuals, the machine would likely just end up on the shelf again. So I settled for a more reasonable choice and got an HP-32S, which I like a whole lot. It turns out that a portrait calculator is just fine for me if the keys aren't as fiddly small as on the 1980s Sharp and Casio models.

[AnnoyedOne]

My own calculator history.

My first scientific was a TI-30 LED. That only lasted a few years, despite numerous attempts at repair by me, when the keyboard became unusable and it was discarded. A common issue with that model.

My next was a National Semiconductor NS-108. It had a "soft" keyboard but also had a mechanical power switch which had started having issues not long after I purchased the unit. I tried to fix it, many times, but after some 9-10 months I gave up and threw it away.

I then purchased a second-hand TI-55 LED from a newspaper classified ad. Unlike the previous two nothing ever failed (keyboard or power switch) but in March 1983 I saw a HP-15C in a shop. I had to beg for money, from a relative, to buy it but did a few weeks later. The (still working) TI-55 went into storage.

I'd seen the HP-41C but it was some 3x the price and didn't have as many "standard" features IMO and was larger etc.

In the summer of 1985/6 (I forget which) I purchased a HP-16C mail-order along with a few coworkers. At the time I was writing assembler code for 8 and 16-bit CPU's so it came in useful at times.

For decades I used both HP's in my career as as a professional EE. They went to work, daily, in a briefcase. To this day both still work although the HP-16C has "LCD bleed" which has never worsened over the decades.

In May 2002 I sold the TI-55 (and manuals), which was still working, on a popular auction site.

Out of pure nostalgia I purchased a used TI-30 in July 2013. A 9V battery unit (no NiCad battery pack or charger like my original). The last time I checked it was working.

This year my interest in the HP-15C was re-ignited and I looked at the SwissMicros DM15L and learned about the HP-15C LE. Then I discovered the HP-15C CE. After a lot of research/reading (here and elsewhere) I bought one in May 2024.

As a consequence of this I experienced nostalgia for the TI-55 and I ended up looking at the TI-55 III. A result of that was that I realised its limitations and discovered the similar HP-20S so I bought one of those in June 2024. Underrated IMO but it is algebraic vs RPN so most here won't even consider it. Plus it is considered a lowly "student" model.

Then a rekindled interest in the HP-12C (I'd never had a need for one) so I purchased a HP-12C+ really cheap in August 2024.

Now I'm back to the DM15L. If SwissMicros releases the 2-line firmware I may be poorer. And here we are some 6-7 weeks before Christmas. Dear Santa...

Probably obvious to many here but my interest is in the HP Voyager models. And to a lesser degree the Pioneers. IMHO they are true (shirt) pocket models. Those before (and after) are more handhelds IMO. Those two models also have LCD's and operate off cheap coin cells. IMO rechargeable's/chargers are more trouble than they're worth.

As an aside I also own two cheap solar only power 4 function units. One is in my car but some months ago it was missing so I bought another cheap. As it turned out I found the first beside the passenger seat. So the new one sits in a drawer unused. The old is a Canon LS-25H II and the new a Casio HS-4G.

A1

[DA74254]

My history.
I do have some 20-30 calcs in my possesion now, but for the "practical/school" use, here's my (somewhat boring) history:
My very first own-bought calculator, in 8th grade (European school-system, so 14 years old), when we were allowed to use calcs at school, was a Citizen (I think) 5-banger (+ - * / SQRT) solar/light powered only. Don't remember the type or full "name", but it was white with gray keys except the =, which was orange.
It took a fall from the desk to the floor (abt 75cm) and the LCD broke.
I then purchased a Casio FX-82 (The black one from 1982), which was apprehended by my sister when she went to Gymnasium.
I had a "blue landscape" Sharp with 10 digit mantissa, bought in 1993 when I started Chief Engineer School, but sold it to a fellow student when I bought my used HP 28S, which took me through said school.
After that, I became a collector/hoarder and bought a HP 49G+ (horrible keyboard), a 35S, a Prime, a 50G, the Elektronica 52 and 61, a Numworks, a few Casios in the FX and CG series. Then the SM's in my signature. My latest purchase was a HP 15C CE.

Which is now my goto? Well, it is spread between the DM32, DM42n, WP43 and HP 15C CE. The Prime gets used occationally, but it is long inbetween.
The other calcs sits without batteries and are mostly just checked every now and then to see that they still function.

[Maximilian Hohmann]

My history...

... began with a Privileg 883 D-ESR-E that I got ca. 1977 in what would be called "high school" in the United States. A colorful non-programmable scientific calculator with green VFD that still works after almost 50 years.

This was followed by a Ti-59 which I got for my last year at school in 1979. I kept it all the way through university (aerospace engineering) and it too still works. Some time in the early 1980ies the Ti-59 needed to be repaired, which was done by Texas Instruments for a very reasonable fixed price but took several weeks. Because I really needed a calculator then I bought the cheapest (scientific) one they had at the library store, a Ti-30 LCD. The keyboard was bouncy right from the day I purchased it and soon some display digits would fail, but it was needed only for a few weeks. I think it still works, but I would have to search very intensively to find it.

Later I bought an Aristo Aviat 618 (ca. 1988) followed by an ASA CX-1 Pathfinder (ca. 1989) when I started training for my second profession.

And this is it, I never needed a pocket calculator at work ever, not as an engineer and not as a pilot either. So I never bought another calculator because I had to.

But the fascination that came with the first calculators never went away and I kept buying calculators because I wanted to. I don't count them, but the total number is way above 1,000.

I aim at a complete collection of HP models (which I know I will never have but I am getting close), I want as many navigation calculators as I can find, I wanted to have all the 300-series Compucorp calculators (success!) and in general I will still buy anything that glows in the dark and has more than "+ - * /" on it's keyboard. The older it is, the more appeal it has for me. Modern time replicas, simulators, emulators and suchlikes are not (yet) in my collection, but the idea of repurposing existing calculators to create something better has some appeal.

Regards
Max

[gentzel]

I think I first became aware of HP scientific calculators from advertisements in Scientific American when I was in middle school. Could also have been Popular Electronics. I sent away for a catalog (likely one of those "circle the numbers and send in the card" things) which ended up being The Hewlett-Packard Personal Calculator Digest (volume 1, 1976). I had a 4-banger (Novus 850) but this was a whole new world. The HP-67 was my dream, but way beyond my middle school budget. And I remember reading about RPN and thinking "Yeah, that makes perfect sense."

I'm not being dramatic when I say that The Hewlett-Packard Personal Calculator Digest changed my life. I still remember vividly reading "Micro-Code: Electronic Building Blocks for Calculators" in volume 3 (1977). That article made me say "This is amazing! I want to be an Electrical Engineer". And while I ultimately ended up in CS instead, the path was clearly started by that publication.

It wasn't until senior year of high school (1979) that I had a part-time job that allowed me to actually purchase one of these miracles. Another vivid memory is driving to Penn State Beaver Campus bookstore to buy my HP-34C. I loved that machine. It was the first "programming" I ever did and was a huge help in my first Calculus course.

Enter college. I don't remember what happened to the 34C, but somehow it was gone, probably stolen (the start of a sad pattern). Picked up an HP-41CV as its replacement and it was a blast. Started to dabble in synthetic programming... until I left it in the common area after a study session. Went back 15 minutes later but it was gone. Sigh...

Next came the HP-15C. Another great calc (though the form factor change took some getting used to)... until it was stolen from my apartment (along with my Olympus camera) during Christmas break. At this point I'd started to shift from EE to CS and didn't have as great a need for a high quality calculator so I did without for a while.

Once I started my first real job, I picked up an HP-28C. Love-hate relationship with that thing. Loved RPL, loved the multi-line display, mostly loved the form factor, hated the extremely small memory. Picked up Customize Your Hp-28 by W.A.C. Mier-Jedrzejowicz. When the HP-28S came out I was both excited and annoyed - only a year later? Really? But I had to have it!

Then came an HP-48SX, then HP-48GX. Great machines (despite the performance issues with the GX UI).

Also at some point someone listed NOS HP-16Cs somewhere (don't recall where). It was just the bare calc+case, with a laser printed manual. Ended up selling that one years later at a significant profit.

Then... sadness. While Meta Kernel, Erable, and ALG48 were awesome, the move to Australia led to the end of decades of great physical machines. Blue plastic? Rubber keys? Tiny Enter key at the bottom? What? I picked up a 49G just to try it, but it was awful. Great software imprisoned by terrible physical design. Its still in a box somewhere, and I don't miss it.

I then ignored HP for years. It was fun to see the 12C become so ubiquitous, and still for sale in office supply stores, but that was the end of the "old HP" from my perspective.

So why did I come back? Well, after years away, I got a craving to replace my old 34C. So I started Googling, and searching eBay, and was somewhat shocked by what I found. HP-15C CE? SwissMicros clones? DB48X? PX41CX? Multi-calc? What??? This is amazing (and potentially expensive)!

And so here I am, reinfected with the HP bug years later. A 15C CE beside me, another on order, a 12C converted to a 16C (with overlay), a 34C arriving in the mail any day now, and I'm sure many more to come.

[peacecalc]

Hi all,

with 16 yaers I got may first calculator a canon palmtronic F-52 with a LCD display. That was in year 1977. I lost that calc and as I was looking for that calc forty years later (for buying it as a vintage calc again), I had to realize that this calc is a very rare vintage calc. I only saw since I was looking for, only one offer at ebay (with a bleeding display). In the year 1982 I began the studies in physics at the university. I was looking for a calc with more possibilities and I found the HP 15c. In that former times in germany the calc had cost 400 Mark. I got it cheaper for 300 Mark. This calc works until today and was a lot in use.
While my profession I was looking for a more ease of handling calc and found the HP 32II. Since 2010 I use the HP 50 the direct opposite ease of handling, but with a lot of joy in programming in User-RPL. The most wired program I made was able to unwrap hulls of 3d structures into 2d.
And now I use th HP Prime G2 since two years.
I'm not a real collector more a playing child which is curious about that calcs. I wasted a lot of money and a lot of time more for this kind of activity, but to be honest, with a lot of fun!

[Garth Wilson]

Mine's at http://wilsonminesco.com/HP41intro.html .

[Geoff Quickfall]

For me in 1975 it was a LLoyds Acumatic 333 with VF display, posted my history of use up to the 41CL here in 2011:

Ode to the calculators I have used.

Of course, many many more as were needed to populate the ‘book’!

And others like the monroe 326 / 392 …

[aurelio]

(10-31-2024 06:46 PM)Geoff Quickfall Wrote:  For me in 1975 it was a LLoyds Acumatic 333 with VF display, posted my history of use up to the 41CL here in 2011:

Ode to the calculators I have used.

Of course, many many more as were needed to populate the ‘book’!

And others like the monroe 326 / 392 …

Geoff, ..the BOOK.... ? .? .? .?

[carey]

(10-31-2024 03:16 PM)Maximilian Hohmann Wrote:  But the fascination that came with the first calculators never went away and I kept buying calculators because I wanted to. I don't count them, but the total number is way above 1,000.

There should be an award for this!

[Massimo Gnerucci]

(10-31-2024 06:46 PM)Geoff Quickfall Wrote:  many many more as were needed to populate the ‘book’!

And others like the monroe 326 / 392 …

THE BOOK!

;-)

[dm319]

This is fun! Interesting to read all of your stories.

I remember first having a calculator when I started 'middle' school, must have been 11 years old. My parents got me a Sharp EL531-GH. I was the only kid to have one in an entire class of Casio fx-82LB fractions. I used to hold a vague sense of superiority as the Sharp had a better algebraic logic and bracket handling, but I think that was my defence mechanism for always being a bit different.

I vaguely recall when I pointed out to my dad, who always had his Casio fx-3800p sat on his office desk, how much faster my calculator was. He irately replied something like 'rubbish!!'. I've always thought of him at that point as being an old man yelling at people with newfangled devices that they claim to be better. But I'm probably a similar age now.

Loyal to Sharp, I eventually went to boarding school around the age of 13, and upgraded to this Sharp EL-506L(/556L). It was a really great machine and I much preferred the functions and UI over the equivalent Casios. I think I broke it at some point and replaced it with the very similar Sharp EL-531RH. You could type in an algebraic expression with letters, and while it wouldn't solve anything, it would calculate the value of it for given values of the variables.

I never saw a single HP calculator at my school. And I think I may have overheard someone talking disparagingly about RPN - much like you'd talk about some kind of comical affliction. That probably coloured my very limited ideas of RPN to something 'weird' or eccentric.

I went to medical school, where you don't really need a scientific, except a little for some pharmacology exams, and some statistics software for research, so while I carried on using the Sharp, it wasn't so important to studies. A lot of interests somewhat died at medical school - I loved my Amiga A1200, but I had to replace it with a Thinkpad running WinXP - and that killed my love of computing. I also loved to compose electronica, but the music school at Cambridge didn't allow me entry because I wasn't a medical student. They are not forgiven.

But now, 17 years later, I shameless geek out about everything I really wanted to back then. My DM42 comes with me to work and clinics, and calculates chemotherapy timing, clinic appointments, days post treatment, BMI, renal function, and any other quick calculations I need to do. I still use Thinkpads, but my A1200 is alive and well, and recapped, and my Thinkpad runs UbuntuMATE linux and it gets a lot of love too.

My eldest son just started year 7 (11yrs), and when he saw the Casio fx-85GT CW, he immediately wanted that. My second eldest will start next year - he is left-handed and can take quite an unconventional approach to thinking, so I believe a DM-15L is winging its way to us, and nearly on our shores.

And the cycle repeats!

[Thomas Klemm]

In the old forum we had a dedicated section for such posts: HP Memories Forum

Quote:This forum is intended to post memories related to HP calculators.

[Steve Simpkin]

My history:

Most of my HP history is listed in a post I made in the Memories forum in 2000 titled: It Still Works As Good As The Day I Bought It. It is surprising how little has changed in the past 24 years.

I used HP calculators exclusively through High School, College and my 40 year career as an Electrical Engineer. There were times in the 1970's, 1980's and 1990's where I used my [current model at the time] HP calculator 5 days a week, sometime 3-6 hours a day. That included the following HP models: HP-25 (1977-1987), HP-11C (1987-1988), HP-28C (1988-1990), HP-28S (1990-1991) and HP-48SX (1991-2018). Now I don't use them that often for work. When I do need a calculator for a quick calculation at work, I grab one of the 7 or so HP, TI and Casio calculators I have sitting near me at all times. When I am not working, I usually use one of my many HP calculator apps on my phone.

[born2laser]

This subject comes up in the forum every once in a while. I think I killed the latest thread when I posted mine
https://www.hpmuseum.org/forum/thread-17...#pid165803

[AnnoyedOne]

(10-31-2024 08:39 PM)dm319 Wrote:  I never saw a single HP calculator at my school.

As I recall there was only one person in school with a HP. Scientific but I don't recall the model. Perhaps a HP-31E or HP-32E. Maybe the latter since I think the owner bragged about it being programmable. Whatever the case it didn't interest me much.

I only had TI's because I could afford them. I didn't love AOS or hate RPN. In fact I don't think I even knew of RPN until I bought a HP-15C. It was never an issue for me either way.

Also, I forgot about the TI Programmer (essentially the same as as TI-30) I had for a time. As I recall it suffered the same fate as my TI-30 (constant key bouncing). The HP-16C is much better.

My uncle taught civil engineering and I once saw a HP on his desk. Probably a HP-25 since he too was a "cheap bastard" and likely wouldn't have forked out extra for a 25C or 29C.

My dad brought a basic 4-function home from work with him each day. A TI Datamath clone I think. I used it a few times to check my school arithmetic homework. In those days one had to write out solutions in longhand so a calculator was only useful to verify your results. I disassembled it a few times and it had TI chips inside (hence a Datamath clone).

I was given a small sliderule in my youth but never used it much.

A1

[ThomasF]

(11-01-2024 10:54 AM)AnnoyedOne Wrote:  

(10-31-2024 08:39 PM)dm319 Wrote:  I never saw a single HP calculator at my school.

Perhaps a HP-31E or HP-32E. Maybe the latter since I think the owner bragged about it being programmable.

Then maybe a HP-33E or HP-33C (or even 34C), since neither 31E or 32E were programmable ...

Just to be picky ...

Cheers,
Thomas

[AnnoyedOne]

(11-01-2024 10:58 AM)ThomasF Wrote:  Then maybe a HP-33E...

Perhaps. Not a 34C. Way too expensive.

https://www.hpmuseum.org/hp33.htm

Too much water has flowed under this bridge

A1

PS: I think that someone had a TI-57. It, and the HP, cost way more than the TI-30 (which was the choice of many as I recall).

[John Garza (3665)]

I blame my father.

I inherited a collection of old fishing lures from him. And since then, I think I've been infected with the 'collecting bug'.

Funny how a utilitarian instrument is somehow morphed into an object of pleasure and desire.
You know, like a Ferrari. Basically it's just transportation. But when it's done really well, like HP calculators, they become something much more than utilitarian.

My path was straightforward:

Junior High School: TI-2550
High School: TI-59
College: HP-67

I still have all three and they are 100% functional.

And then I go nuts and start collecting.


-J

[vassilisprevelakis]

In the late 70s, while at high school, I wanted to buy a programmable calculator but could not afford an HP-67, so I went for the TI-59.
Then I pestered my father till he bought me a PC100C print cradle for the TI-59 and I was pretty happy with my system, but my TI-59 had problems with its keyboard (mainly not registering keys).

When the HP-41 came out I sold my TI-59 and PC100C and got an HP-41C.

That HP-41 had problems from day 1: it would work fine for short periods of time, but if left running a long program, it would eventually crash. Thankfully, the problem was repeatable, so I went to the dealer and left it with them overnight running a simple program, and the next morning I went back to show them that it had crashed. They replaced it immediately, and I still have this calculator with me. After 40+ years, its only problem is that one of its keys no longer makes the click sound but still makes contact, so its OK to type. I suspect that the the dome has cracked, but the plastic is still holding it in place.
In the 2000s I bought a NOS HP-41CX and I am using that instead.

Together with a fellow student and long time friend (hi ji) we were developing programs for the European Users library, and we got lots of goodies for our efforts. I recall getting a quad memory module, a time module and a Wand from UPLE. I also bought a PPC ROM, so with the Wand and card reader, my HP-41C was fully expanded. Sadly I could not afford a printer or HP-IL interface, till the early 2000s and eBay. I remember porting the bar code generator program to my BBC home computer, and modifying it so that it would blink the CAPS-LOCK LED on the BBC keyboard. Then I would attach the Wand over the LED with blue tack and trick it into thinking it was reading barcodes.

In the early 80s, while at university, I bought an HP-34C because I loved the LED display and the integration facility. Didn't do much with it because my HP-41C was far more capable and would run longer due to the LCD display. So after a couple of years I sold it to a fellow student.

In the 90s, my old friend, ji, gave me an HP-28C. Although the huge number of keys were a definite asset, I found the HP-28C infuriating. Eventually I gave up on it and put it aside and never used it since. Its probably still somewhere in my apartment in Greece, but I have lost track of it.

In the 2000s, I was working in the US, and had the opportunity to buy lots of HP-41 related stuff over eBay (the golden period when prices were OK), so I got an HP-IL interface, printers, floppy disk drives and so on. So now my collection is fairly complete. I never bothered with the HP-IL tape drive, since I got a great deal buying four HP-9114s. I got them really cheap since they were not working. Their only problem was their battery packs which needed new batteries. I also cleaned and lubricated the floppy eject mechanism. So I had 3 9914As and one 9114B.
I have the 9114B here in Germany and I think I got a glimpse of one of the 9114As at ji’s home. The remaining two 9114As are probably in Greece with the rest of my Series 80 collection (that's another story).

From the late 70s till the early 2000s my HP-41C was my constant companion, functioning as a primitive PDA, alarm clock, calendar, the lot. Nowadays I no longer carry it with me, but its still on my desk for quick calculations.

I never bothered with the HP-42 as I viewed its lack of external storage a big problem. However, I recently bought a DM42 from SwissMicros, which I am slowly getting familiar with.

Vassilis
http://www.series80.org