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HP 19C and HP 10 potentiometers
12-16-2017, 11:31 PM
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HP 19C and HP 10 potentiometers
I recently found this old HPMuseum thread: Adjusting HP 10 and HP 25C and realized it is exactly what ails one example (decimal dot HP logo version) I own. This unit works great, but the chracter spacing is about 1/2 the width it should be.

When I opened it up, I found NO potentionmeters. It is clear that someone in the past had tinkered with the boards and probably removed the pots. I have a parts 19C that had extreme battery corrosion and this board (battery contact board) only has two pots. I don't see where 5 pots would fit on my examples.. On my parts machine, I have one pot on the edge of the board and one near the (-) terminal. Examining Tony D's circuit diagrams from HPCC point me to two pots. A 200k version and a 50k version.

I happened to have a 50k pot and added this to the board where it should be, but no change to the printed character spacing.

Did anyone ever see photos or the article published from this thread that ID the pots?
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HP 19C and HP 10 potentiometers - aj04062 - 12-16-2017 11:31 PM

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