old & rare? HP35:Help needed to repair

[isanchez]

Dear Didier and Dieter,

thanks for your helpful comments.

I have installed the board in an HP45 and it WORKS perfect

Regarding the BUG (2.02 ln e^x=2): YES, it has the bug.

As the board works, seems that the problem is located in the display board. I can get a 45 as donor. I would like to keep the 35 original board as much as posible (not fully replacing it by the 45 one, as a first approach to the solution)

I am not sure where to start: by the cathode or the anode? Do you have any idea, taking into account the calculator behaviour?.

Seems that the cathode is fully compatible with HP45, but not the anode, but not sure about this.

Again, thanks for your help!

Kind regards

Ignacio