Calculator blog

Musings and comments about our common interest


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The HP30b

Now that I am working a lot with the HP Prime, using the little tips and user keyboard, I am getting used to the low displacement, clear click of the HP Prime family. "When was the last time I felt a click like this?", I ask myself. And the answer is clear - in the Hp 30b Financial Calculator.

This little machine has never enjoyed the cult status of the other machines: both the 12c/cp family (with their classic keys with three functions in each, and programmable in RPN), or the HP17bII+, with its very good keyboard feel and intelligent solver, which can be turned in a programming language with a little knowledge and ingenuity, have enjoyed a "top" status that the 30b did not reach.

And the 30b is the fastest of them all, and as well the one that has a better set of functions - but that you know only when you have bought it, not before. Its menu system, while not as "beautiful" as the one from the HP17bII+, is well organized, and you can perform solver-like calculations in one of its mini-solver 3- or 4- variables calculator. You can even perform Black and Scholes calculations off-the-shelf - a first for an HP calculator. Both the HP12c and the HP17bII could do it; the first one, fully using the 99 memory steps (in a program made, I think, by Pablo Fernández, engineer and Finance professor in IESE MBA); the second one, via some complex programming of the solver. 

But as well, it is the ideal statistical calculator. Apart from creating lists of points, which is much better that just feeding some accumulators like the previous calculators did (apart from the HP17bii), it has a set of "descriptive statistics", another set of data fit in many types (many more than the ones that appeared in the statistic pacs of the HP 41c), then the typical accumulator set (that we have from the very first HP calculator that had statistical functions) and another set of quartile analysis. If you look at the manual (pages 69 and onwards) you will see all of them in a very clever "function map". 

The front panel is made obviously made of plastic - the metallic aspect, while elegant from far, and resistant to scratches, fools no one. It cannot be compared with the nicer livery of the HP17bII. 

The screen, while much more descriptive than the one on the 12c family, has an alphanumeric upper part (where you see the function you're performing or the place in the menus your into now), and a numvrica part, but not made of dot-matrix characters, but with segments instead. Curious. It is much clearer than a dot matrix display, but it seems odd in these times of "retina" displays.

(I always forget to state that one of the advantages of a calculator is that it is nearly impossible that it runs out of power while you're at a critical situation like an exam. I almost also forget to tell you that it can be algebraic OR RPN !!)

We have lowered its price to 40€. Now we have plenty - probably more than what we could convert to wp34s (which is another of the beauties of this little machine!). I leave here a good picture of it, for you to enjoy.

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Más sobre: hp 30b, wp34s
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Collector's Pack

As many of our visitors are calculator collectors, we have decided to make their hobby easier, by joining all HP calculators in four groups:



We are adding all calculators in each group and reducing their price by 20%. In that way, we increase the size of the sale, and you get a significant discount. In the case of the first of them, the financial pack, you save 97,86 €! (apart from lower shipping costs)

The financial pack is composed of:



HP12c Platinum

HP12c Anniversary




In later days we will complete the offer with the other bundles. I hope you like it!


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WP 34s just born


I received this week the overlays from Eric Rechlin. Wonderful quality and choice of material. You cannot touch it from where you are - believe me that feeling is good and adherence superb:


I have received several overlays. I plan to set the complete kit: the flashed HP30b + the overlays. Just to Europe to avoid competition with Eric; and 10 € of each sale will be donated to the wp34s project.


Now, let's see the machine under surgery:


It was updated with the latest available build, 1125 at the time:



Now, let's see how it ended up:


Sorry - the light condition was low and my pulse unstable -> fuzzy picture.

This one is better:

When you do it, do not try to fix it with a hard thing - see the mark over the CLx key.

I learned from it and the rest of the keyboard was excellent!!

It really looks professional, and the key feel is much better than the HP20b.

Now, let's try to work with it and make some programs !!!

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New flashing service

Today I have received a USB to com adaptor. Since most of our computers are laptops and quite new, we did not have serial adapters. I have then proceeded to update a 12c+ with the latest available software. In this particular case, it did not increase speed (it was already 150 times faster, so I am not deceived), but it corrected a number of issues compared with the original firmware.

We have decided to offer firmware flashing as a service for our purchases of a calculator. It will have a 10 € charge. The rules:

  • Calculators elegible for firmware flashing are HP10bII+, HP20b, HP30b, HP12c (ARM version)
  • The customer supplies the firmware through email.
  • The calculator to be flashed will be a new, out-of-the-box (or plastic package!). The serial number and proof of purchase bits of the packaging will be included in the shipping to the customer. (It is the customer decision to register the calculator in HP's website). Sorry, we will not flash calculators not brand new!

One of the most exciting projects is the repurposing of the hp20b and hp30b financial calculators with ultra-slick scientific firmware. The project is called wp34s and is run by Marcus von Cube, Walter Bonin and Paul Dale (in no specific order!).

You can find it on

There have been a number of releases (build number was 800 at the time of writing), and you can check whether you like the software by running the included .exe file and testing the features. The .exe file has the advantage of having the right labels on the keys!

I have not yet tested the flasher cable and software on a HP30b but I plan to do it shortly. I will then report on the results!

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