HP-21 repaired

[PANAMATIK]

(06-20-2017 08:35 PM)rprosperi Wrote:  Another great repair story Bernhard, thanks for sharing it. The HP-21 has a special place for me, as this was my first HP Calculator. I really wish I had kept that one, but I sold it to buy an HP-25C, and it has only spiraled out of control since then...

My first HP- calculator was the HP-25. I didn't know about the existence of the HP-21 calculator until some years ago. When I saw it the first time I thought: very peculiar how naked it appeares without any printing on the keyboard bezel and only one blue prefix key! Now I really like this calculator.

My next restoration will be another HP-21, with both display drivers and ACT chip defective and need to be replaced. But this is a child's play now.

Bernhard