HP35 and serial numbers?

[jonteague]

So I acquired a 35 V4 at the weekend, fully working and in quite good condition with the original plastic case and power supply. Sadly missing the battery pack but only slight sign of corrosion from leakage, not enough to be a problem (anyone know a UK supplier of battery packs? I can't find one.)

As you can see definitely a V4.

   

The label on the front is however missing the "35", a V4 should have that right? This was a long time ago used in a university so I guess it could have gone back for service and if some student had picked at the label maybe HP put on whatever they had? I presume this can't be as it came out of the factory or are there any other photos of a V4 with the wrong label?

Also, the 5 button has a dimple on the top, research suggests the V4's did not have that?

My real question though is about the serial number which is 1143A34635 - again I didn't think V4's had that as it's the number of the earliest runs? Or did HP start using old numbers if they happened to have the labels lying around?

   

[AndiGer]

I have a v2 here, serial 1143A30831. Not so far from your serial.
It has the split battery case as yours seems to have too.
Mine even has the black battery connector near the power plug (connector not visible in your picture).
And mine has a different back label. Title: HP-35 INSTRUCTIONS
No Made in USA … bottom line.
Yours seems to be a newer back label.
Front side mine has the flat power switch.
And the 2.02 bug.

[jonteague]

No 2.02 bug on this one (unsurprisingly as it's v4) but it does have the arc cos/sin/tan of low values bug (anyone know if that's expected on a v4?)

I've just re-read the collecting page on here and note 1 says there is one other v4 with a 1143 serial number known - two now I guess - and the suspicion is it was a number swap. Did HP do this when units went back for service?

https://www.hpmuseum.org/collect.htm#early1