On Fri, Sep 2, 2022 at 05:25 AM, Adrian Godwin wrote:
> There's one (maybe more) exception to this: On HP pocket calculators, the date code?IS?the year and week of manufacture.
I don't think that's true, at least not universally.
I have several HP35s with the date code 1143 and it appears many were made with this number - too many for a week's batch, I think.
ref : http://www.vintagecalculators.com/html/the_hp-35_calculator.html
I'm the one who went out on a limb with that statement. I don't have any direct knowledge of this; my understanding is based on an email conversation I had with the owners of . I had emailed them to try to explain how I thought the HP serial prefix coded the year and week of design finalization, and they claimed that this was not true in the case of handheld HP calculators. I took their word for it.
It seems quite possible that early calculator production followed the established HP pattern, but later production might have changed. Your HP-35s are quite early, while mine are much later. But both of mine share a common serial prefix, 1346A. I agree that the sequential numbers, 12108 &?15956, seem too high for one week's production.
OTOH, I have two HP-45s, with serial prefixes that differ by 1: 1349A and 1350A. The sequential serial numbers, 16002 &?34910, make me wonder if the prefix changed but the sequential serial numbers continued uninterrupted.
Does anyone know how many calculators HP could produce in a week?
Bonus question: What 3 key combination press does what on an HP-35? Likewise for the HP-45? (Note: it takes practice to be able to depress all 3 keys at exactly the same time.)
