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HP Forum Archive 04

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46 Printer Problem
Message #1 Posted by Katie on 12 Nov 2000, 11:40 p.m.

Hi all,

I'm in need of some repair advice. I have an HP-46 that's in fine shape except that the printer sometimes prints the wrong data! Specifically, every few lines it will print one or more characters that are one position past (on the print wheel) what it should be printing in that position. For example, instead of a "1" you might get a "2" once in a while. The problem occurs more frequently when the digits are sequential (i.e., 1.23456789) and hardly ever occurs when they're all the same (e.g., 8.888888888). Also, it almost always occurs (on one or two lines) when printing the list of registers regardless of their contents.

I gave the printer mechanism a really good cleaning and lubrication, but this had no affect other than to make it a bit quieter. So I don't think it's a mechanical problem. Any idea of what's wrong here? Is the printer logic somehow losing track of the position of the print wheel? Are their speed/timing adjustments that can be made to the circuit? (The problem does seem to occur more often when the printing is fast, like in the case of the register listing.)

I've looked through the 9805 service manual (it's got a very similar printer), but it's no help at all.



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