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HP Forum Archive 19

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OT: For the (oops!) AOS lovers among us
Message #1 Posted by Frank Rottgardt on 16 Mar 2009, 7:34 a.m.

For the AOS lovers among us:

in november 2008 the university bookstore in Saskatchewan still had some HP-20s on stock for a reasonable price? On request the send items also abroad. Don´t know how difficult it is nowadays to get hold of new unused HP-20s. Maybe all are sold by now.

Check out:

Price list university bookstore

Greetings from Sweden // Frank

      
The underrated hp-20s
Message #2 Posted by hugh steers on 16 Mar 2009, 9:00 a.m.,
in response to message #1 by Frank Rottgardt

I agree, the hp-20s is a great little calculator, if you can survive without RPN.

A while back, I acquired a new one thinking it wouldn’t be long before you couldn’t buy new anymore. It struck me as a great little scientific calculator for normal use – and it’s programmable, which has become a rarity nowadays.

The screen is very clear (segments) and the keys work well. Mine had that hp quality build you don’t get anymore and reasonably priced.

All in, I think the 20b has been mostly overlooked and is generally underrated. I think this is because it doesn’t do anything particularly outstanding. However, in today’s world, most things are afflicted with some problem or other that makes things worse. This calculator does what it says on the tin and it works.

The idea of pre-storing some ROM programs for problems like solve, integrate and matrices, although somewhat of a cop-out, are actually a welcome bonus on a machine that otherwise would not have this function at all.

            
Re: The underrated hp-20s
Message #3 Posted by Marcus von Cube, Germany on 16 Mar 2009, 11:18 a.m.,
in response to message #2 by hugh steers

I've picked one up some time ago in an auction. It's somewhat battered and it has an electrical instability that makes it crash to an extend where only shorting the battery terminals helps. Sometimes a software reset/keyboard test makes it work again; sometimes not. As a former AOS customer (my first full AOS machine was an SR-56, its predecessor in my possesion, the SR-51A had only multiply/divide/exponentiation before addition/subtraction and no parenthesis) it was just interesting to see what HP did in that area. The chain mode only business models are somewhat disgusting in this respect.

The 20S is a nice little programmable calc. Today, looking at key codes instead of mnemonics isn't much fun but for a frequent user, this may become second nature (as it was for me back in my SR-56/TI-59 days.) Today an HP-21S has arrived. It seems to work flawlessly and will replace the 20S in most cases where I want to play around with a programmable AOS machine from HP.

I'm still looking for a 27S...

                  
Re: The underrated hp-20s
Message #4 Posted by Walter B on 17 Mar 2009, 2:41 a.m.,
in response to message #3 by Marcus von Cube, Germany

Quote:
Today an HP-21S has arrived. It seems to work flawlessly and will replace the 20S in most cases where I want to play around with a programmable AOS machine from HP.
The 21S is a really unique little calc, replacing a lot of statistical tables in most compact and portable format. It sits on my office desk for that reason. If it only had a ALG/RPN switch, I'd avoid erasing results by putting in the next argument for calculation ... ;-)
            
Re: The underrated hp-20s
Message #5 Posted by DaveJ on 16 Mar 2009, 5:27 p.m.,
in response to message #2 by hugh steers

Quote:
I agree, the hp-20s is a great little calculator, if you can survive without RPN.

A while back, I acquired a new one thinking it wouldn’t be long before you couldn’t buy new anymore. It struck me as a great little scientific calculator for normal use – and it’s programmable, which has become a rarity nowadays.


Rare?
Casio have no less than 5 current programmable non-graphing models:
http://www.casio-intl.com/calc/programmable/

The old 50-F has just been discontinued, but still available in plenty of places:
http://www.casio-intl.com/calc/programmable/past.html

Dave.

                  
Re: The underrated hp-20s
Message #6 Posted by bill platt on 16 Mar 2009, 5:49 p.m.,
in response to message #5 by DaveJ

I don't think they sell any of them in the U.S.

                        
Re: The underrated hp-20s
Message #7 Posted by DaveJ on 16 Mar 2009, 6:00 p.m.,
in response to message #6 by bill platt

Quote:
I don't think they sell any of them in the U.S.

I believe that's correct, but when has that ever stopped anyone in todays global market?

You can't buy my uWatch in the US, but probably 80% of my customers are from the US.

Dave.

                              
Re: The underrated hp-20s
Message #8 Posted by bill platt on 16 Mar 2009, 8:23 p.m.,
in response to message #7 by DaveJ

Um, no sizable number of people will go hunting for programmable calcs. They will simply buy what's on the shelf, assume there is no such thing and use their computers.

Uwatch etc are afficianados.

                                    
Re: The underrated hp-20s
Message #9 Posted by DaveJ on 16 Mar 2009, 9:59 p.m.,
in response to message #8 by bill platt

Quote:
Um, no sizable number of people will go hunting for programmable calcs. They will simply buy what's on the shelf, assume there is no such thing and use their computers.

Uwatch etc are afficianados.


Of course, I wasn't talking about the general population, just pointing out there are no shortage of non-graphic programmables out there. The small number of people who really need or want a non-graphic programmable calc will have little trouble finding or buying a current model.

Joe Average would assume a programmable calc these days is one of the big graphics one, as that's all that is on the shelves in most places I suspect.

Dave.

                                          
Re: The underrated hp-20s
Message #10 Posted by bill platt on 16 Mar 2009, 10:01 p.m.,
in response to message #9 by DaveJ

But I do find it curious why the US is conspicuously absent from marketing plans. Why are Americans not interested, or perceived as not interested in programmables? Why is the rest of the world interested?

                                                
Re: The underrated hp-20s
Message #11 Posted by DaveJ on 16 Mar 2009, 11:01 p.m.,
in response to message #10 by bill platt

Quote:
But I do find it curious why the US is conspicuously absent from marketing plans. Why are Americans not interested, or perceived as not interested in programmables? Why is the rest of the world interested?

I remember someone on here saying some time back that it had to do with the US education policy(s) or something to effect, so there is effectively zero market in the US by way of some form of quasi-regulation?

Dave.

                                                      
Re: The underrated hp-20s
Message #12 Posted by bill platt on 17 Mar 2009, 12:12 a.m.,
in response to message #11 by DaveJ

Schools are run at the local level in the US. There is no national policy except for bribery--and the overwhelming majority of money for public schools comes from local, followed by state. Of course almost no school district would eschew the federal handouts but it requires all sorts of stuff---the latest federal initiative is called "No Child Left Behind" and has to do with testing and school performance...

There is certainly no consistent calculator policy across the U.S. for schools.

There is a national policy (not government) regarding professional engineer license tests--it is a private testing company with national scope which forbids graphing calcs but allows programmables as long as they have no I/O and no QWERTY--which has evolved to a "permitted list" which included the 33s and 35s.

But no other programmables in wide circulation is interesting though I think the reason may be that other areas have an education market that uses them? Just a thought.

            
Re: The underrated hp-20s
Message #13 Posted by DaveJ on 16 Mar 2009, 7:27 p.m.,
in response to message #2 by hugh steers

Quote:
I agree, the hp-20s is a great little calculator, if you can survive without RPN.

I agree too, I like the 20S and used it as my daily work calc for some time.

Two annoying things got to me though, the exponent key being shifted was a huge mistake, makes it tedious to do engineering work. It should be were the backspace key is IMO.

The other thing was the annoying "E" display for the exponent, it is not obvious at a glance. Underscore or a space should have been used instead.

It's available in two colour schemes too, mine is the less appealing (IMO) green and purple.

Dave.

                  
Re: The underrated hp-20s
Message #14 Posted by hugh steers on 16 Mar 2009, 8:49 p.m.,
in response to message #13 by DaveJ

Why did they do that - the shifted E? clearly a design error.

Also biggest thing that hacks me off with the 71b is the shifted delete key. shifted delete!! what were they thinking?

                        
Re: The underrated hp-20s
Message #15 Posted by DaveJ on 16 Mar 2009, 10:01 p.m.,
in response to message #14 by hugh steers

Quote:
Why did they do that - the shifted E? clearly a design error.

I'm at a loss as to why any scientific calc would have a shifted E key. I can't imagine it ever getting past any sensible design review meeting... Oh, now I get it...

Dave.

                  
Re: The underrated hp-20s
Message #16 Posted by Karl Schneider on 16 Mar 2009, 11:53 p.m.,
in response to message #13 by DaveJ

DaveJ stated,

Quote:
The other thing was the annoying "E" display for the exponent, it is not obvious at a glance. Underscore or a space should have been used instead.

I agree about the 'run-together' mantissa and exponent in the low-end Pioneers with 7-segment LCD's, but I suspect that the reason was to provide more uniformity of source code between Pioneer models. The other models displayed such numbers the same way, but the dot-matrix displays of the mid- and high-end Pioneers allowed a more distinct "E" to be displayed. Subtle detail: The HP-32S displayed a full-size "E", but the HP-32SII displayed a reduced-size "E".

Hugh Steers stated,

Quote:
The idea of pre-storing some ROM programs for problems like solve, integrate and matrices, although somewhat of a cop-out, are actually a welcome bonus on a machine that otherwise would not have this function at all.

I suppose that having these functions as keystroke programs in ROM is better than not having them (especially for marketing!), but here are the fundamental problems with the HP-20S implementation:

  1. Usage and protocol of the special functions is not at all intuitive, so the manual would generally be needed.

  2. Suppose that the user has programmed a function, evaluates it at a few points, then wants to integrate or root-solve it. The user initiates the special function in PRGM mode through the LOAD function, and -- poof! -- the user's function in program memory is wiped out. That kind of impractical silliness would have been kept out of the HP-15C as an unwavering design objective.

-- KS

Edited: 16 Mar 2009, 11:55 p.m.

      
Re: OT: For the (oops!) AOS lovers among us
Message #17 Posted by Ron G. on 16 Mar 2009, 11:49 a.m.,
in response to message #1 by Frank Rottgardt

No need to call. I called 'em up, and was told they don't have any.

            
Re: OT: For the (oops!) AOS lovers among us
Message #18 Posted by nacho on 16 Mar 2009, 7:53 p.m.,
in response to message #17 by Ron G.

I love My 20S with RPN ;)

http://img10.imageshack.us/img10/6825/18012008134s.jpg

Edited: 16 Mar 2009, 7:55 p.m.


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