Sick HP-11c


I have an HP-11c that's not firing up. I checked it's innards to see if anything was amiss, but everything seems firm and in one piece. I hooked up external power, and it worked(!) However putting in a new set of cells resulted in either "Pr error" or nothing at all on the LCD - and the keys did nothing. I suspect it's sucking too much current from the cells... Any ideas? Any recommendations for a repairer ?? (Preferably UK) Thanks guys.



there was a thread here some time ago,
which discussed that topic.

You could short-circuit the battery terminals for a second,
then try again.
I had this feature a while ago on my 11C.
After I put a paper clip between the terminals for a second,
and then installed the batteries, it worked fine.




If it is drawing too much current (and that's something that should be checked with a milliammeter) then it might be that one of the
chips has gone leaky (and the machine is essentially unrepairable unless you have another broken machine to raid the chip from) or you might be lucky and
have a leaking electrolytic capacitor (which is cheap to replace). I've had the latter problem in a couple of Pioneers but never (yet) in a Voyager.
As regards a UK-based repairer, where are you? I do a few repairs, but I don't like sending the machines by post if I can avoid it (for the obvious reasons).


Thanks for your help, Ray and Tony. It looks like the old "paper clip" trick worked! I made an over complicated guess about current drain based on the fact that the HP-11c fired up from an external source (which was capable of providing a higher current than a few button cells, of course). Thanks again, guys.

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