The HP-35: Consumer Electronics, an Origin Story

> The HP-35 had numerical algorithms that exceeded the precision of most mainframe computers at the time. [...] This forced time-consuming manual comparisons of results to mathematical tables. A few bugs got through this process. For example: 2.02 ln e^x resulted in 2 rather than 2.02. When the bug was discovered, HP had already sold 25,000 units which was a huge volume for the company. In a meeting, Dave Packard asked what they were going to do about the units already in the field and someone in the crowd said "Don't tell?" At this Packard's pencil snapped and he said: "Who said that? We're going to tell everyone and offer them, a replacement. It would be better to never make a dime of profit than to have a product out there with a problem". It turns out that less than a quarter of the units were returned. Most people preferred to keep their buggy calculator and the notice from HP offering the replacement.

And here is a scan of that recall notice: https://imgur.com/K1k0cSQ (original source: http://www.hpmuseum.org/forum/thread-2821.html)

At my dad's workplace, every scientist had a Friden 55. The managers compared the price of the HP to the annual service contract on the Friden, and bought an HP to try out. They were going to let each scientist have it for a week, then pass it on to the next person. Instead, after just a couple weeks, the Fridens were all in the dumpster.

It's proving a little tricky to find a picture and/or more info about the Friden 55. All I'm getting is other models. Was it mechanical?

(Hopefully some of them ended up in attics, they sound mildly interesting even if just from a historical-interest retrospective standpoint)

I understand not everyone buys calculators, but that’s sort of the point of the article that this was marketed as a ‘consumer’ electronics product rather than scientific equipment.

Also there’s much less friction and much more marketing today, but it’s wild to imagine how millions of iPhones ‘move’ in a single weekend, every year for nearly the last decade and what is required to keep supply in pace with demand.