Help in choosing a new calculator

[bhennink]

My HP27 died due to a failing keyboard and I am lookin for a replacement. Tried the 50G which was a mismatch for me and I did not like it at all.
I do not like RPN I prefer arithmic input

I had in the 27s a lof of solver equations with one drawback. There was no naming of equations and you could not reorder equations.
For a new calculator i would like an option to group calculations, if a caculator with such options exist.

passive component caculations
Filter calculations
Stepup converter calculations
Thermal calculations
etc.

it this is possible, that would be extremely helpfull

I want longer variable names so I do not want to be limitted to one char names

I hope to find some advise or more info here before I decide.

[Jlouis]

You can set the 50g to algebraic and it will do whatever you want.

But if you mean you didn't like the program language, which is RPL, maybe you can try the HP 35s, set it to algebraic and the keystroke program for it is not difficult, although I don't know if it compares to the HP 27 you are used to.

Another option is find a HP27s, it has a powerfull algebraic solver and if think it has 7kb of memory, but it is a little bit hard to find ( only used in auction sites) and more expensive than the 35s.

Good luck, and keep us informed of your search.

Cheers

JL

[bhennink]

Hi Jlouis,

Tried the 50g and used it in arithmic mode, the equation lib that comes with the 50G does not work. I am not sure where RPL comes in use for me I am not planning to write programs.

creating an own equation was not to difficult and worked. But I could only have one equation in memory and could not find how to save equations.
I also had something pretty strange with it.
I would like to share the image but do not know how to upload it I can olny use an URL

Actually id do not mind to upgrade to something more fancy. After more the 20 years using the 27 that idea could make me happy I just do not want to loose the capabilities I have now.
That is why the 50G came in my vision and also the prime or even some TI calcs. But I prefer a HP one.

But it should at least be capable to do what my 27s could do

[Marco Polo]

What you write makes me think you just gave a quick look to the 50g.
Anyway I think that the 50g is an overshoot for your needs.
I would give a look to the 35s. If I am not wrong, it can be configured both as algebraic and rpn.
You can write your own equations and store them but you cannot name them.
Variables name are single letters.
Solver is good, IMHO.

Hope it helps
Regards.

Marco Polo

[bhennink]

(09-18-2016 02:59 PM)Marco Polo Wrote:  What you write makes me think you just gave a quick look to the 50g.
Anyway I think that the 50g is an overshoot for your needs.
I would give a look to the 35s. If I am not wrong, it can be configured both as algebraic and rpn.
You can write your own equations and store them but you cannot name them.
Variables name are single letters.
Solver is good, IMHO.

Hope it helps
Regards.

Marco Polo

Hi Marco Polo,
Single letter equations is not a good option for me. A step back from the 27S.
I get the feeling the 50G indeed an overshoot.
The prime seems capable to do lot of what I want and a lot more from what I heared.
but maybe there is a simpler version between the HP35S and the HP50g?
solver in the 27S was always great
HP39GII? HP40GS or are these no longer actual?

Thanks sofar

Bert

[Marcio]

(09-18-2016 02:59 PM)Marco Polo Wrote:  What you write makes me think you just gave a quick look to the 50g.
Anyway I think that the 50g is an overshoot for your needs.
I would give a look to the 35s. If I am not wrong, it can be configured both as algebraic and rpn.
You can write your own equations and store them but you cannot name them.
Variables name are single letters.
Solver is good, IMHO.

Hope it helps
Regards.

Marco Polo

I will second that. And with a little imagination you can name equations using the EQN features, ie, another equation.

IDEAL GAS LAW
PxV=NxRxT
---
RELATIVITY
E=MxC^2
-----

and so on. The 35s has plenty of memory so you should be able to create a large library of equations.

I do the above to identify long-term stored programs which will accept one letter only:

T - TRAPZD AREA
M - MATRICES
G - CMPLX DECOMP
D - DERIVATIVES
etc...
and then the equations I use regularly. I think it's neat.

[bhennink]

Hi Marcio,
I relay want multi char variables. Sometime I have equations that are pretty similar for different Hardware components . And no names and single char makes it hard to recognize for which part it is. Even with multichar variables this could me a challenge
So the 35 will not work for me. As said. A step back from my old 27

[Marcio]

An HP-42s will let you use multi-lettered variables but it's RPN only. Equations are entered as programs.
It seems you will have to get a graphing calculator. If that is the case, skip the 39g/49g (they are not the best hardware) and get an HP-Prime. It will do all you have described and much more.

[Marco Polo]

(09-18-2016 04:38 PM)bhennink Wrote:  Hi Marco Polo,
Single letter equations is not a good option for me. A step back from the 27S.
I get the feeling the 50G indeed an overshoot.
The prime seems capable to do lot of what I want and a lot more from what I heared.
but maybe there is a simpler version between the HP35S and the HP50g?
solver in the 27S was always great
HP39GII? HP40GS or are these no longer actual?

Thanks sofar

Bert

It seems you should find another 27s :-)
I am a very long term RPL user (almost 30 years.....)Rh
The HP48SX was my tool at the university and at the beginning of my career.
Now I use a 50g and a 48gx with some additional ram.
Frankly speaking I strongly prefer the 48gx as the 50g is too much aimed to symbolic calculations and I do only numerical.
The real limit in your possibility of choice is the algebraic, which strongly limits the choice in HP world.
In your shoes, I would give the 50g a second chance. It is a very powerful tool, customizable and fully programmable.
I never used in in algebraic mode....
You can find plenty of software for it and, installing one of the several equation managers, you can archive and recall all your equations very quickly.
Furthermore, the 50g memory can be organized using directories just like any personal computer.
Once tried, it's hard to find something better.

[Ron Ross]

I sympathize with your loss of your Hp 27s. The Hp 35s is not an adequate replacement for you. You need to find another Hp 27s or have yours fixed. Both are costly options.
.
If you cannot find an Hp 27s, the Hp 19B or 19bii are probably good options. The downside is a clamshell which is a more fragile calculator in a somewhat larger case (not nearly as large as an Hp 50G though). Another downside is algebraic w/o precedence (called chain logic).

You might also consider an older Ti 85 or Ti 86 (though newer than your Hp 27s). Both will feel much closer to your Hp 27s than anything Hp now offers (aside from the Hp keyboard click). Admittedly these are graphing calculators, but a bit slimmer than the Hp 50G and better laid out for your needs.

Casio made some older pocket programmables, but they were also all single letter variable calculators too (I believe).

Let us know which option you decide to pursue and if you choose something other than another Hp 27s, what your feedback is.

[bhennink]

Hi Marco,
I will certainly try again if I can get used to RPN with an 48 emulator on my phone.Rules of entering are a bit different and juist typing an eqution and '= 'to see the result is just more easy to check what I calculate.

But anyway I still want a real calculator with proper keys

Just discovered a colleague in an other building who has a 50G which he does not use much. I will can to borrow this and give it another try. Strange thing is he never used with the solve function. (only as standard calculator which is killing a fly with a canon) So he cannot help me
I have to go on a trip tomorrow so I do not have much time this coming week but after that I will sure try.

But how can I store an equation in algebaric mode . I can enter an equation . I can solve it but in which stage do I STO it
I open EQW:

Enter an equation (it is visible in reverse

Now I cannot enter STO.

When I press enter it starts solviig the equation

In the top line I see the equation and the lines below the variables.

Here on the top line: I press STO and an name -> invalid syntax.

If I start editting here and press sto I can enter a name, ->invalid syntax.

Maybe I just had a malfunctioning one or bad luck while trying. I was also a bit in a hurry because of my running project and breaking down of my 27S. I washed the keypad with alcohol and it is functioning again but of course that is only temporary.
Like applying contact spray on a switch.

[rprosperi]

(09-19-2016 12:57 PM)Ron Ross Wrote:  I sympathize with your loss of your Hp 27s...
If you cannot find an Hp 27s, the Hp 19B or 19bii are probably good options.

Also, look at the HP-17BII. It can be used in RPN or Algebraic modes, and also has the exact same solver as the 27S. It does support the L() and G() functions properly, unlike both later 17BII+ versions.

It can be found easily on eBay or elsewhere for MUCH less than a 27S, however it does not have financial functions built-in (but they can be added in the solver). Like the 27S it is also a Pioneer series model, so the hardware and keyboard are the same great feel as the 27S.

[striegel]

(09-19-2016 11:10 PM)rprosperi Wrote:  Also, look at the HP-17BII. It can be used in RPN or Algebraic modes, and also has the exact same solver as the 27S. It does support the L() and G() functions properly, unlike both later 17BII+ versions.

It can be found easily on eBay or elsewhere for MUCH less than a 27S, however it does not have financial functions built-in (but they can be added in the solver).
...

I think you meant that it doesn't have the *scientific* functions built-in. The 17BII is a financial and business calculator first and foremost.

[rprosperi]

(09-20-2016 12:09 AM)striegel Wrote:  I think you meant that it doesn't have the *scientific* functions built-in. The 17BII is a financial and business calculator first and foremost.

This is exactly correct, it is indeed primarily a financial calculator. However the OP has never said what functions he needs (e.g. maybe needs trig?), but has stressed using the 27S solver, which is the same in the model.

So, I am just pointing out this model for him to look into in case it does provide what he is looking for. It would be a shame to miss hearing about this inexpensive but excellent model if it does meet his needs.

[Marco Polo]

(09-19-2016 01:15 PM)bhennink Wrote:  But how can I store an equation in algebaric mode . I can enter an equation .

i can't help you with algebraic mode.
In rpn is quite straightforward:
1) enter you equation as 'x+y=z' (whatever). Remember the '
2) press ENTER
3) type the name of the equation
4) press STO
DONE!

Pressing VAR you have access to memory. You should see the name of the equation in one of the softkeys. Just press it to recall the equation on the stack.

Anyway, I suggest to read the manual..... ;-)

[bhennink]

Mi Marco,
This did the trick.

I missed the quotes. When I put them around the equation it works

I searched for this in the manual but could not find it there
I went trough the PDF in the chapter about solver but there was no discription how to store and I got lost in the chapter about storing Variables

[Vtile]

(09-20-2016 09:27 AM)bhennink Wrote:  Mi Marco,
This did the trick.

I missed the quotes. When I put them around the equation it works

I searched for this in the manual but could not find it there
I went trough the PDF in the chapter about solver but there was no discription how to store and I got lost in the chapter about storing Variables

Also the equation writer (EQW key or down arrow for equations in stack level 1) is a handy tool for more complex equations you need / want to type in algebraic format. It works in algebraic (RPN/ALG setting doesn't matter) so you do not need any '-marks there, it also have a few handy features like simplification, evaluation and factorising all of them can be done for specific parts of equation IIRC.

It does have pretty steep learning curve, note also that the CAS system separates the numbers differently in exact mode if the number do have dot in the end like 100. in your "exact" equation will turn it as approx equation and you always get floating answer. This is one trap for new players.

Also if you do program in approx mode the numbers in the program source are turned to approximated values (dot added at the end) when the program is pushed to the stack to wait to be storaged, something that can cause a much frustration until you figure out what is causing the "problem".

Same approx behaviour goes with the symbolic solver, if you enter equation (just an example) F=0.5*m*v^2 and try to solve the m it solves it as aproximated and simplified answer and doesn't give you that made in paper style visual format (which you were expecting because you did set the calculator to "exact symbolic answers" mode ) while answer is correct it is sometimes handy to get the calculator turn the values around for you to double check (or for those days when head is pool of jelly) your work in paper or in somewhere else.

Also one feature to test out are the units system in this family of HP calcs. Don't ask how to attach them to your own equations, because I have no idea.

It seems that you are also after some electorics compononent and design calculations, I suggest you take a look for the set of programs one gentleman in Maxim Integrated (can be found atleast at hpcalc.org or https://www.maximintegrated.com/en/desig...ors/hp50g/) have written for 50g.

PS. You are correct 35s is step backwards (in many ways) from earlier top-line models of HPs non-graphing calcs. Which is sad since in business models there still are models (ie. 17bII+) using many of those (UI & management) features with reduced suitability engineering and science because of lack of scientific&engineering features (excluding the business calculus).

[striegel]

If you absolutely needed to get that same item, there is a 27S for sale on the Cleveland Craigslist, but the seller is asking $200.00 for it.

Hewlett Packard HP-27S Scientific Calculator w Original Case and Manual

[Visu]

(09-17-2016 10:19 AM)bhennink Wrote:  My HP27 died due to a failing keyboard and I am lookin for a replacement. Tried the 50G which was a mismatch for me and I did not like it at all.
I do not like RPN I prefer arithmic input

I had in the 27s a lof of solver equations with one drawback. There was no naming of equations and you could not reorder equations.
For a new calculator i would like an option to group calculations, if a caculator with such options exist.

passive component caculations
Filter calculations
Stepup converter calculations
Thermal calculations
etc.

it this is possible, that would be extremely helpfull

I want longer variable names so I do not want to be limitted to one char names

I hope to find some advise or more info here before I decide.

The 35s might be a good option at a decent price. Though purist won't consider it as a true HP. But it offers a lot and certainly matches your demands.

[Marco Polo]

(09-20-2016 09:27 AM)bhennink Wrote:  I missed the quotes. When I put them around the equation it works

I just tried again on my 50g in algebraic mode.
Even easier.....
- Type the equation (even without quotes)
- press STO
- type equation name
- press enter

I recommend you to play as much as possible with the 50g before spending thousand of euros in a used 27s. You may find that the 50g meets you needs at a fraction of the cost.

Beware: the 50g, compared to the 48gx or the pioneer series, is a real battery eater