HP31E Missing Pin

[AndiGer]

(03-15-2021 12:16 PM)ThomasF Wrote:  Hi again,

Just checked on my HP-31E, and yes, 2 out of 3 chips (the silvery ones) are both missing pin 8. Doesn't show very well in the picture, but locking close I can see that the pins are missing. My model is the original, clamped version i.e. not soldered, and the pins are really cut, not burnt away.



And yes, the device is in excellent condition, works like a charm!

EDIT: Found these notes as well, in this case (a HP32E) only two chips are present - no dummy (without pin 8) was present in this device.
https://www.keesvandersanden.nl/calculat...pair_2.php

Could it be that to keep the correct pressure between the pads and the pins, HP included dummy chips to fill the compartment that are normally used in other models? I also noticed that the chips are marked - in my case only the first chip has readable identification - but the other two was just covered in silver paint.

Cheers,
Thomas

Interesting observation. Have a not working 37e lying around for several years and never realized two chips only with 7 legs. Both 00031 SGP80008.
3rd chip black, no. unreadable