So .. this one time, I was involved in a project to replace a thousand dumb terminals RS232 lines with ethernet throughout a labyrinthine maze of inner ducts and panels and routing networks and old-school inter-building telecoms cable channels, and so on. A job considered worthy of me, per the senior operators, since I had failed to find the bugs in the RS232-link that had necessitated (triggered) this upgrade to ethernet in the first place, greybeard grin. I didn't write the RS232 code they were using, I just complained about it too loudly this one time and it was, therefore, forever mine.
As a result of those bastard operators and their fetish for overalls, I can still do base-T muscle memory in the dark, and .. this one particular time .. finding myself buried deep in some dusty fan-duct that had required circus-like machinations to get into, stringing cables in the guts of the building .. my only flashlight falls out of my mouth and breaks itself on one of the thousands of sharp pointy things keeping building tiles from falling on us in places like banks with high ceilings and hospitals with low, dense ones, and so on.
So for a second I glimpse darkness and ponder the future 15 minute ordeal getting back across the ducts and to our exit-spot mostly blind and having to follow my new cable run by hand and make sure everything was set.
I foolishly yell back to my fellow duct-puller colleague, a relatively untrustworthy teenager like me at the time, who - doing an apprenticeship "network operation" at 3am in the morning, sitting there waiting for us to immediately leave after this - has absolutely no time for my shit and wants to get down from the ladder we have wisely put on top of another ladder in the depths of the basement, in order to get access to this ceiling hell-hole in which I was in danger of inhabiting permanently.
He sticks his head barely through the ceiling tile, up at me, and throws the only thing he has at hand with a light, his HP calculator, somehow chucking it right at my general direction long enough that I can see the thing and reach it before he stops letting dim light in around his neck, and so .. I type in 8888888 and use its feeble display light to crawl my way back through the ducts, a foot at a time .. to check my cable run .. by hand.
And, inevitably, those little dinky LED's help me find a kink in this one particular 'infamous' RS232 bundle which, unawares to us dopey copper tuggers, had been a key link in the chain leading to our brand new ethernet cable going in at an angle, cable shield cut open on a steel duct blade edge, which also had remnants of the old RS232 bundle, the missing trunks. WTF.
So .. by law .. we had to pull another length of cable, so back I go, down the precarious ladders bearing super bad news, past the fuming fellow dungeon crawler and our boss, getting wind of the troubles our ladders were in, and so we got the spare flashlight out of the van, another hour or so off schedule before the early-birds come to work .. and back into the depths, one more time, dagnabit.
Well, for weeks after that, I thoroughly loved annoying the greybeard operators that I, geniously, debugged the network problems with a calculator. Fellow junior op got his HP back, but I still don't think he'll know how to use it.
You might find BOFH a worthy soak of attention if you haven't already:
I see no overlap between the stories, even if they are about the same people.
On the same site, there is
http://www.hp9825.com/html/osborne-s_story.html
with what Tom Osborne says about the history of HP-35. That gives additional details, but it is also distinct from the parent article.
Short summary: "I want that in my pocket"
The several paragraphs in the parent article corresponding to specifically that web page start at:
> Tom Osborne, a Berkeley-trained electrical engineer, wasn’t one of those 9000 employees. In his Bay-area apartment, he had built a floating-point electronic calculator he called the Green Machine (after the color of the automotive touch-up paint he used on the balsa wood case). He tried shopping it around but no one was interested until he showed it to HP in June, 1965.
Thankfully the power supply still works so I can take it out every so often and enjoy the history of it.
1. take out batteries
2. fill a shallow container with IPA (70% or 90% is ok)
3. immerse buttons, but try and keep the display out of the IPA as much as possible (if liquid gets in the display it takes forever to dry and can leave a ring)
4. work the buttons until you feel improvement, IPA will turn brown
5. let dry for a few days before you put batteries back in.
Computers don't get old. Their users do.
It doesn't matter how old the computer is, there is a user out there, somewhere.
(Disclaimer: kept every computer I've ever used/owned/developed-for since 1978.. I know for sure my HP is in some hallow box, somewhere..)
Ah, so you could connect this pocket calculator to mains power? Guess it shows that I'm from the generation who grew up with LCD-equipped calculators, which could run for years with two button cells...
The early calculators, which had either LED or vacuum fluorescent displays, could use either a few R6 cylindrical batteries or an external power supply, like a laptop today.
When close to a wall plug, it was normal to use it, because the lifetime of the batteries was modest, mostly due to the high power consumption of the display.
While this was a disadvantage, bright and fast VFD displays were much more appealing than the dull and slow LCD displays that have replaced them a few years later.
I believe that HP has used only LED displays at that time and not VFDs, because they manufactured the LED themselves, unlike other calculator vendors.
nickel-cadmium has entered the chat, installed first in the HP-35!
When I got to grad school, I bought an HP (forget the number) and it was trash. I had spent all that money and it was no better than the cheap foreign junk. I was so angry I gathered folks in the lab at a certain point and threw it against a wall to smash it. I wrote to HP, enclosing some of the pieces and telling pretty much this story, and telling the how disappointed I was in their calculator. This was the old days, so somebody actually wrote back with a candid answer that told me that they realized they had a poor design process, but that I should buy one of the new generation. (I was hoping for a discount price, but no go on that!)
So I bought an HP15C. I still have that thing, and it works perfectly. (I've had 2 other HP calculators since, and of course they are better in lots of ways, but I like my old HP12C more.)
I would have none of this attraction but for the RPN feature. The physical aspects of the machine were great and all, but it was really RPN that let me calculate correctly without always thinking I had got lost.
Nowadays I always have a laptop handy and just type in a REPL to do a lot of simple calculations.
PS. before I do any calculation, I do it in my head so I have a very rough idea of the answer. I do that in class quite a lot, and I think my students view this as some kind of magic trick.
Here is a relatively recent review of the main Android options: https://www.hpmuseum.org/forum/thread-22091.html
I own, err, three. Use one, hedge the others on going up in value one day :)
Now, if someone could explain to me the logic behind the naming of the HP-10, HP-10b, HP-10C and HP-10s, I’d be most grateful...
"I was a bit concerned about the stack architecture and RPN notation, but that all went away when I demonstrated one of the first prototypes to my mother-in-law, who is anything but a mathematician. After I had done some fairly complex operations, Fran said, "How many things can you stack up in that machine?" With that comment, my worries disappeared."
Starting with the infix a+bc
The tree form of that is:
+
/ \
a *
/ \
b c
a b c * +