The joy of helping others

[Jurgen Keller]

From time to time I get a request for advice about how to repair an HP calculator that died or doesn't work properly anymore. I always try to answer those questions to the best of my knowledge, also searching this forum for related information. Recently it was an HP-15C that stopped working. One of my tipps was that it might be a contact problem. Today I've got the answer that cleaning the contacts really solved the problem and the calculator seems to work fine again. That's always a nice moment of satisfaction. The spirit of sharing knowledge and trying to help others is one of the things in this forum that I like most. Unfortunately, I currently don't have much time to participate in the discussions. Anyway, thank you all for making this forum such a valuable and helpful place of information, it inspires me to spread this spirit in my personal life, too.

[Garth Wilson]

I think we have all benefited tremendously from technical forums. I miss the paper magazines and catalogs of decades ago; but reader interaction was slow, requiring waiting for the next issue to see readers' responses. I exchanged paper mail with other subscribers too, but again it was very slow, and including pictures usually required finishing a roll of film and getting it developed, then making the extra prints to send. It was fun back then, and it's fun now; but we definitely have luxuries today that we didn't have back then.

[Hans-Peter]

Hallo Jürgen

After my easy repair of a HP97 with somme faults (resistors, transistor, printer roller and card reader), I have my HP65 own defective candidate. At power-up only a short flickering of one digit. The current consumtion looks quite normal.
No corrosion, clean contacts, no visible damage an no idea what's going wrong.
I tried using the schematic to make voltage measurements, but I did not get any further.

Is there any help in universe?

Schöne Grüsse aus Basel
Hans-Peter

[Jurgen Keller]

(01-12-2017 10:22 PM)Hans-Peter Wrote:  I have my HP65 own defective candidate. At power-up only a short flickering of one digit. The current consumtion looks quite normal.
No corrosion, clean contacts, no visible damage an no idea what's going wrong.
I tried using the schematic to make voltage measurements, but I did not get any further.

Is there any help in universe?

I have to admit that I have no good advice in this case. Maybe a bad display driver or a bad capacitor? The only thing I can offer is to check if I have a spare (and working) CPU board so we probably can track down the problem.

Maybe you should also consider to post your question in the General Forum to make it more visible.