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Hello everybody,

I just acquired 2 Woodstock financial HP-22 calcs.

The oldest one, most probably because of an heavy corroded circuitry, did not work very well even after a 50/50 alcohol vinagre/water bath of a few hours and a good brushing job. Probably due to the PCB itself, corroded inside, it will be very difficult to make this one alive again, unless I open the PCB itself, which seems hazardous.

Before having washed the other one (a most recent model whom components are quite different, corroded as well, or so), I had tested the first one with this other and recent PCB.

In this case, everything is working on the older calc, unless the registers R0 to R9 (and associated functions like 'FV', 'SIGMA+', etc. that require the use of the registers 5 to 9, and that return '0.00'). Number entry "seems" correct since '123' is returned as '123.00', but there is no mean to recall (RCL) another number than '0.00'.

I shall post some pictures next week end.

Does anyone know which component failed? Is there a way to fix this?

Many thanks in advance!

Edited: 11 Feb 2011, 1:12 p.m.

Two HP-22 calcs; the older one is at left.
One can see that not only components are differents, but boards too.

I just tested the recent one after having brushed it yesterday, it works perfectly. IMO it would be a shame to dismantle it.

So I am only searching for another old HP-22 to make some replacement on the older one. But which one?


(sorry for picture's quality: flash on my camera behaves curiously, not really at the same time than the snapshot itself).