what do you think of the HP 92?

[dmh]

I recently acquired a very nice HP 92 and have had a quick look through the manuals and a bit of a tinker with it and so I thought I'd check out the information here on the forums and was surprised to find very little information on this model (that, or search is failing me).

Are these rare?

What do you think about this model?

What's great / good / bad?

My first desktop HP (was actual hoping it was a 97 but alas) and initial impressions are:

- really like the huge clear LED display

- like that it includes basic calendar functions and can print DOW. The LED display while calculating is great too :-)

- the keys are noisy / clanky / springy and not like normal handheld HP keyboards

Your thoughts?

[Maximilian Hohmann]

Hello!

(02-02-2022 08:02 AM)dmh Wrote:  Your thoughts?

Lucky you :-) This is indeed a very rare calculator and one of the few LED models from HP that I could not add to my collection yet. So far I have an Hp97 and an Hp91.

The keyboard: Yes, it is different from the handheld models and can give a bad first impression, but actually it is excellent for working. Many years ago (must have been 1982?) I did an internship with a company that made, among other things, attitude control thrusters for satellites. They put several binders of vacuum-chamber measurement values and an Hp97 on my desk and made me analyse the data and derive some quality indices from it. It took a whole week, eight hours a day, of constant keyboard action to process those data. I have never before or after manually entered so many figures into any machine, be it pocket calculator, desktop calculator or computer and really came to like that keyboard! No bouncing or missed keys ever. At that time I mainly used my Ti59 and that was quite different in this respect. With my Ti that task would have probably taken me two weeks.

The display is just perfect for a desktop calculator. No comparison with modern LCD ones. Readable from all angles and in almost all lighting conditions.

Regarding the printer: Personally I never cared about these toy printers that use cash-register thermal paper which fades within some months and is too toxic to be recycled together with normal paper. In these HP desktop computers the printer is usually the first thing that will break. Fixing it is very very difficult if not impossible due to the nonexistence of spare parts. Have a look at the threads regarding this topic, especially the contributions of teenix. So if yours still works don't overuse it - it will not last forever.

Regards
Max

[Steve Simpkin]

Dr. William Kahan had a lot to say about how great the HP-92 was and why it was not more successful in the marketplace. In summary:

“So you’ve got to understand that the HP-92 was a gem in that it worked so flawlessly on everything. And you’d get a good printed record. Yes, well, so we were defeated by the marketing guys on two fronts. We didn’t get them into the libraries because they weren’t willing to make the big print manuals. And we didn’t get them out there in large numbers when they would have been the newest and hottest thing. We couldn’t get them out there because the price was too high, and lowering the price afterwards doesn’t really change people’s opinion. What they remember about things is first impressions, you see. You only get one chance to make a first impression. “

Dr. Kahan had more to say about the HP-92, HP-27, HP-34C and particularly the HP-15C in the following oral history.

http://history.siam.org/pdfs2/Kahan_final.pdf

[Dave Britten]

I don't have a 92, but I have a 97, and based on how much I love the 97, I'm sure I'd love the 92! The one thing I wish the 97 had, though, is a "print disable" option that would go so far as to make the "print X" and "print stack" instructions behave like on the 67 (i.e. display-only instructions).

[teenix]

(02-02-2022 03:34 PM)Dave Britten Wrote:  I don't have a 92, but I have a 97, and based on how much I love the 97, I'm sure I'd love the 92! The one thing I wish the 97 had, though, is a "print disable" option that would go so far as to make the "print X" and "print stack" instructions behave like on the 67 (i.e. display-only instructions).

Thanks for the idea Dave, I will add it to the next 97 CPU board code release.

Maybe [f][f][Print Stack] etc. would be easiest.

cheers

Tony

[rprosperi]

(02-03-2022 01:20 AM)teenix Wrote:  Thanks for the idea Dave, I will add it to the next 97 CPU board code release.

Maybe [f][f][Print Stack] etc. would be easiest.

This is a great idea, but would be much more useful if it could be a global toggle, e.g. pressing [f][f][Print Stack] the first time sets a mode where 'print x' and 'print stack' only display the value, then pressing [f][f][Print Stack] the next time restores the default mode of actually printing, so that this mode can also affect behavior in a running program, in addition to when calculating interactively at the keyboard.

[Dave Britten]

(02-03-2022 01:35 AM)rprosperi Wrote:  

(02-03-2022 01:20 AM)teenix Wrote:  Thanks for the idea Dave, I will add it to the next 97 CPU board code release.

Maybe [f][f][Print Stack] etc. would be easiest.

This is a great idea, but would be much more useful if it could be a global toggle, e.g. pressing [f][f][Print Stack] the first time sets a mode where 'print x' and 'print stack' only display the value, then pressing [f][f][Print Stack] the next time restores the default mode of actually printing, so that this mode can also affect behavior in a running program, in addition to when calculating interactively at the keyboard.

Right, in a program is where it would be useful, so a toggle like this would be the way to go. And maybe have it automatically go back to print mode when it's powered off to reduce "Why isn't my printer working?" confusion.

Maybe use the key sequence f-paper advance? That little button doesn't have any shifted function, as far as I know.

[teenix]

(02-03-2022 01:44 AM)Dave Britten Wrote:  

(02-03-2022 01:35 AM)rprosperi Wrote:  This is a great idea, but would be much more useful if it could be a global toggle, e.g. pressing [f][f][Print Stack] the first time sets a mode where 'print x' and 'print stack' only display the value, then pressing [f][f][Print Stack] the next time restores the default mode of actually printing, so that this mode can also affect behavior in a running program, in addition to when calculating interactively at the keyboard.

Right, in a program is where it would be useful, so a toggle like this would be the way to go. And maybe have it automatically go back to print mode when it's powered off to reduce "Why isn't my printer working?" confusion.

Maybe use the key sequence f-paper advance? That little button doesn't have any shifted function, as far as I know.

Thanks for the input, it seems I would be better making a new program code. There are still a few reserved ones and that way they can be saved to cards and program files.

These spare codes are rare commodities, so I might make it work as:

C register = 0 then Program Code([f][f][C]) = OFF
C register = 1 then Program Code([f][f][C]) = ON
C register = X then other things can happen using the same program code.

It would take 2 program steps to turn ON or OFF and of course it could be done in normal RUN mode as well. At power on, it would default to OFF.


On an off topic note, my work was cut short the other day as I flew into a 19KV power line during low level survey. The wire was spanning between two hill tops and hanging at 47 meters above ground just where I happen to be. I normally fly 35 meters above ground in this type of hilly terrain but was climbing to get to the peak of the next larger hill. It was totally invisible until about one second away (70 meters or so) and and then it hit the prop and starboard wing. It was lucky, it could have turned out really nasty although the aircraft needs some major repairs. It is true what I've heard, if you see a power line in front of the aircraft you're going to hit it.

cheers

Tony

[Massimo Gnerucci]

(02-03-2022 03:24 AM)teenix Wrote:  Thanks for the input, it seems I would be better making a new program code. There are still a few reserved ones and that way they can be saved to cards and program files.

These spare codes are rare commodities, so I might make it work as:

C register = 0 then Program Code([f][f][C]) = OFF
C register = 1 then Program Code([f][f][C]) = ON
C register = X then other things can happen using the same program code.

It would take 2 program steps to turn ON or OFF and of course it could be done in normal RUN mode as well. At power on, it would default to OFF.

Still waiting for my board since - as it entered Italy - seems to be hidden somewhere...
This printer handling would be a useful improvement to the instruction set.

(02-03-2022 03:24 AM)teenix Wrote:  On an off topic note, my work was cut short the other day as I flew into a 19KV power line during low level survey. The wire was spanning between two hill tops and hanging at 47 meters above ground just where I happen to be. I normally fly 35 meters above ground in this type of hilly terrain but was climbing to get to the peak of the next larger hill. It was totally invisible until about one second away (70 meters or so) and and then it hit the prop and starboard wing. It was lucky, it could have turned out really nasty although the aircraft needs some major repairs. It is true what I've heard, if you see a power line in front of the aircraft you're going to hit it.

Whoa Tony! I am glad that all went well, even if with damages to the plane.
I am sure it was an unpleasant experience.

[teenix]

(02-03-2022 06:57 AM)Massimo Gnerucci Wrote:  Still waiting for my board since - as it entered Italy - seems to be hidden somewhere...

I think sometimes it is pot luck if mail gets though on time these days, especially overseas. Some countries seem to be overloaded or there is limited or no freight room on aircraft and have stopped delivering parcels.

cheers

Tony

[Dave Britten]

Back on the subject of the 92/97/etc., I really like the keys they used on the Topcat models. Pretty much all my other LED units have needed at least a little (or a lot of) keyboard contact cleaning, but the 97 is flawless. And the buffered input works great.

It's also rather fortunate that the battery packs aren't too hard to rebuild. I just cut open the old pack, removed the old cells, and put some metal contacts at each end so I can drop in a set of 4 sub-C NiMHs. When I need to recharge, I just pull them out and stick them in a typical smart charger.

But there is of course the matter of Achilles' printer gear...

[rprosperi]

(02-03-2022 03:24 AM)teenix Wrote:  Thanks for the input, it seems I would be better making a new program code. There are still a few reserved ones and that way they can be saved to cards and program files.

These spare codes are rare commodities, so I might make it work as:

C register = 0 then Program Code([f][f][C]) = OFF
C register = 1 then Program Code([f][f][C]) = ON
C register = X then other things can happen using the same program code.

It would take 2 program steps to turn ON or OFF and of course it could be done in normal RUN mode as well. At power on, it would default to OFF.


On an off topic note, my work was cut short the other day as I flew into a 19KV power line during low level survey. The wire was spanning between two hill tops and hanging at 47 meters above ground just where I happen to be. I normally fly 35 meters above ground in this type of hilly terrain but was climbing to get to the peak of the next larger hill. It was totally invisible until about one second away (70 meters or so) and and then it hit the prop and starboard wing. It was lucky, it could have turned out really nasty although the aircraft needs some major repairs. It is true what I've heard, if you see a power line in front of the aircraft you're going to hit it.

cheers

Tony

This implementation is way better than I guessed; using new codes making it available inside a program is awesome, providing total flexibility and enabling a program to behave any way you want. Nice plan Tony.

About the off-topic note - HOLY #%#$^%! That's an amazing story, and both you and we are so lucky you are able to relate it here. Is it right to assume the cable broke, and thus you were able to continue flying (straight to the airport I also assume)? What kind of plane were you in, sounds like you picked (or own?) the right kind, a real testament to it's sturdy construction. I would have never guessed contact with a power line could be safely survived. When I was learning to fly in the 70's these power lines spooked me more than anything else, but yours is the first, first-hand story I've heard. We're all thankful the incident was as benign as it was, you are a very lucky guy!

[KimH]

(02-02-2022 11:30 AM)Steve Simpkin Wrote:  Dr. William Kahan had a lot to say about how great the HP-92 was and why it was not more successful in the marketplace. In summary:

“So you’ve got to understand that the HP-92 was a gem in that it worked so flawlessly on everything. And you’d get a good printed record. Yes, well, so we were defeated by the marketing guys on two fronts. We didn’t get them into the libraries because they weren’t willing to make the big print manuals. And we didn’t get them out there in large numbers when they would have been the newest and hottest thing. We couldn’t get them out there because the price was too high, and lowering the price afterwards doesn’t really change people’s opinion. What they remember about things is first impressions, you see. You only get one chance to make a first impression. “

Dr. Kahan had more to say about the HP-92, HP-27, HP-34C and particularly the HP-15C in the following oral history.

http://history.siam.org/pdfs2/Kahan_final.pdf

YouTube has a bit of this as well - Kahan 2016 - it starts at about 2:16

[teenix]

(02-03-2022 01:33 PM)rprosperi Wrote:  What kind of plane were you in, sounds like you picked (or own?) the right kind, a real testament to it's sturdy construction. I would have never guessed contact with a power line could be safely survived.

Cessna 210 for this particular job. Some have 15,000 airframe hours and considering the terrible pounding they take at low level for up to 12 hours a day, Cessna sure did their sums properly. I wonder if they purchased HP-35's when they came out :-) I don't think back then this generation of planes were expected to fly into the next century, but here they are. Sadly, we have had a fatal with a main spar breaking (unheard of) and a lucky escape where the wire tore into the wing cutting the aileron cables. Birds cause problems also. It's amazing how they can get though the propeller disk unscathed, and then hit the windscreen. One guy got knocked out when one came through. Lucky he had a co-pilot.

cheers

Tony

[Paul Berger (Canada)]

(02-03-2022 07:26 AM)teenix Wrote:  

(02-03-2022 06:57 AM)Massimo Gnerucci Wrote:  Still waiting for my board since - as it entered Italy - seems to be hidden somewhere...

I think sometimes it is pot luck if mail gets though on time these days, especially overseas. Some countries seem to be overloaded or there is limited or no freight room on aircraft and have stopped delivering parcels.

cheers

Tony

After some anxious waiting, mine arrived on the west coast Jan. 31 and is currently crossing the country supposed to be delivered Monday..
Paul.

[rprosperi]

(02-03-2022 09:22 PM)teenix Wrote:  

(02-03-2022 01:33 PM)rprosperi Wrote:  What kind of plane were you in, sounds like you picked (or own?) the right kind, a real testament to it's sturdy construction. I would have never guessed contact with a power line could be safely survived.

Cessna 210 for this particular job. Some have 15,000 airframe hours and considering the terrible pounding they take at low level for up to 12 hours a day, Cessna sure did their sums properly. I wonder if they purchased HP-35's when they came out :-) I don't think back then this generation of planes were expected to fly into the next century, but here they are. Sadly, we have had a fatal with a main spar breaking (unheard of) and a lucky escape where the wire tore into the wing cutting the aileron cables. Birds cause problems also. It's amazing how they can get though the propeller disk unscathed, and then hit the windscreen. One guy got knocked out when one came through. Lucky he had a co-pilot.

cheers

Tony

Nice solid airplane, a shame it's fatal... I've never heard of a broken main spar from an incident like that, though to be fair, I've never heard of an incident like that, where the pilot brought it back to a safe landing.

Sounds like your nerves survived the impact OK, did your pants fare as well? Must have been a realllly frightening experience, glad you've some through OK.

[teenix]

(02-03-2022 10:18 PM)rprosperi Wrote:  Sounds like your nerves survived the impact OK, did your pants fare as well? Must have been a realllly frightening experience, glad you've some through OK.

Ha ha, I was training a new chap for terrain flying, I have to "stay cool". A pilot has two sides to the face, only one half that the passengers see.

I did have a passenger once when doing aerobatics, he was not so lucky in the trouser department ;-)

cheers

Tony