HP-19C Power Switch

[teenix]

Hi all,

I wonder why HP decided to put the PGM position before the RUN position on the HP-19C power switch.

I would have thought it would be better the other way around, so that with only click of the switch it is in RUN mode, instead of having to go through PGM mode first.

cheers

Tony

[Steve Simpkin]

My best guess is that since OFF and RUN are the most commonly used positions of the switch, you can just slide the switch all the way to the left or right to for normal use. If RUN was in the middle, you would need to carefully slide the switch from OFF to the middle RUN position every time you wanted to use it for normal calculations.

[John Garza (3665)]

(07-26-2023 07:14 AM)Steve Simpkin Wrote:  My best guess is that since OFF and RUN are the most commonly used positions of the switch, you can just slide the switch all the way to the left or right to for normal use. If RUN was in the middle, you would need to carefully slide the switch from OFF to the middle RUN position every time you wanted to use it for normal calculations.

Yep, I came to the same conclusion years ago. Good old HP usability engineering to the rescue!

-J