I wonder if anyone has noticed a funny coincidence regarding the HP-16C: its model number is 16, very appropriate for a first HP calculator to support hexadecimal integers.

I've always felt sad that HP never created another calculator along the lines of the 16C.

-Ernie

Hi;

I've been wondering a few times about caclculator model # and I never got to a "pattern", if there is one. And I saw a few at the MoHPC that end with a "6" other than the HP16C (46, 56, 66 and 86), all old fashioned, desktop models. But this called my attention, too.

It's not a rule, but many companies use the last digit in their equipments' model # as sort of an ID for their particular purpose. Three HP calculators with a "7" as the last digit are financial, but the well known 67/97 counterparts are not. Both HP22 and HP12C have their model # ending in "2" and are financial, but the 32, 32S and 42S are not. There are many model # ending with "1", "2", "5", "7" and "8". A few others with "0", "4" and "9" as the last digit. But I saw only the HP33E/C and the HP83 with a "3" in the end.

The fact is that the HP calculators are split in two major groups: financial and scientific. Both have their graphics versions, so I don't thing a graphic calculator belongs to a graphics group, maybe I'm wrong. But the HP16C is a class by itself, and if we take those three desktop, old fashion 46, 56, 66 and 86 off the score, the "6" in the end is also an exclusive ID number.

Cheers.

Luiz:

Nice analysis, but I wanted to point out the coincidence between the "16" in "HP-16C" and hexadecimal base (base 16).

Was this a mere coincidence, or was it intentional?

-Ernie

HI, Ernie.

That's intriguing, isn't it? I wrote previous post thinking precisely on this coincidence. If it is intentional, at least in the Voyager series, they may be sure that some guys noticed that. Unfortunately, it's not usual, so we als consider a coincidence. The only thing I noticed is that in most cases, as the second digit "grows", the equivalent calculator is more powerfull. If we think of the Voyager series, both HP15C and HP16C are the ones.

I think the 16 as an hexadecimal reference and the 16 as an ID for the calcualtor is intentional, but based on what I wrote previously, it's not exactly usual in HP calculator models.

Cheers.

I did a little (text) file of the different HP calcs vs time. From this it looked like the numbers went in little series in a very ad-hoc way. e.g. 28,48,38,49 or 41,42,32 (in date order).

It would be interesting to know how HP came up with the numbers... i.e. Mr H or Mr P?, sales?, engineering??

>It would be interesting to know how HP came up with the numbers... i.e. Mr H or Mr P?, sales?, engineering??

They must have used a random number generator, for all I know. Otherwise I can't figure out how come their _first_ calculator was number "35".

-Ernie

If you count the HP-35 keys, you get 35. The calculator prototype had 35 keys, or so the legend goes on, Bill Hewlett christened the calculator as HP-35. The rest is history.

Many classics have a 35-keys keyboard, including the HP-41. Later models had more keys.