Calculator blog

Musings and comments about our common interest


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Offer HP Prime and other calcs

There is an offer that has past unnoticed, since I have not written it here and this is one of the most seen pages in the whole site.

This is a promotion valid for Spain and France. There is a 30# cash refund by HP for the HP Prime, and a 15€ refund for these other models: HP35s, HP12c, HP12c Platinum, HP12c Anniversary, HP17bII and HP39gII

You just need to go to the respective HP web sites:



And follow the instructions therein. The offer ends on September 30.

Due to the countries it is aimed to, I will repeat this in the languages I can:

Hay una oferta que ha pasado desapercibida, ya que no la he puesto en este blog, que es de las páginas más vistas del sitio.

Esta promoción es válida para España y Francia. Hay 30€ de reembolso por parte de HP para toda compra de la HP Prime, y 15€ para los siguientes modelos: HP35s, HP12c, HP12c Platinum, HP12c Anniversary, HP17bII y HP39gII. Sólo se necesitan seguir las instrucciones en las páginas de HP:

La oferta termina el 30 de septiembre.


FRANÇAIS: Il y a une action HP qui est passée inaperçue, peut-être parce qu’elle n’a pas été expliquée dans ce blog, qui est l’une des pages plus visitées du site.

La promotion est valide pour la France et l’Espagne. Il y a 30€ remboursés par HP pour tout achat d’une HP Prime, et 15€ par les modèles suivants:HP35s, HP12c, HP12c Platinum, HP12c Anniversary, HP17bII et HP39gII. Il faut seulement suivre les instructions à la page HP suivante:

Le fin de la promotion c'est le 30 septembre.


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Two different types of HP19bII

I have now received another calculator for the "harem": an HP 19bII with the back door. 

I have fond memories of the HP 19bII. While my first calculators were HP (spice models, beginning with the 33c), I did my last 3 years in university with a Casio pocket computer. At the time, I did not have the funds for the HP41cx - which was the model to have. However, for all practical purposes, the Casio was a better calculator: it could be programmable in Basic and I could do any numerical programming I was asked in my engineering courses. While I missed the powerful Basic of the HP85, with which I made my first money, it was good enough for me.

When I finished engineering I started an MBA. I then got some more money, and I bought the then best available financial calculator - the HP19bII. I enjoyed it during 2 years. It had all the financial tools, plus a good set of statistical and mathematical tools. However, at the middle of my second year in the MBA, it fell to the floor and the battery door went off. I was not able to fix it properly. Tired of sticking it with tape every now and then, I left it in a drawer (from where it was picked up by my sister) and got an HP 17bII instead. A classy machine as well, but missing key features like trigonometrics. Well, it was more than good enough, but it market my end as a self-respecting engineer.

Several years later, when at a covneience store in Madrid, I saw a stack of blister packed HP19bII. They looked blacker than I remembered, but at that time I was not looking for another calculator, and I passed by. I did not know at the moment that I was looking at the back door HP 19bII.

When I started collecting calculators again, the 19b was one of the first to get. I knew what to expect: a well specified calculator, with all the functions I could need for a non-academic environment (seriously, how many times are you inverting matrixes in real life?), but I knew as well that it should rest on my desk most of the time, unless I wanted to have another battery door casualty.

I have just bought a back-battery door HP19bII. I guess that many of you would like to see both kinds compared:


Front view: the back battery door on the right. It shows a darker colour, but the difference is not too big.

Here is the reason for getting it: the back door:


The batteries were set in place with the door, but there was pressure on the door all the time. Whoever changed a set of batteries onthese machines know what I am referring to. This design change solves the problem (at  least, this problem!)

The keys have the same good key feel - totally different from any other HP but very satisfactory. This sample was made in Indonesia.

The keys are much blacker than the original:


A closer look:


Now that I think about it, I have not tested it for speed differences - and I will not do it today. I keep most of the claculators in the collection without battery, to avoid corroding the terminals, and to do these tests I would have to go through the painful exercice of changing the batteries again...

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