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HP Forum Archive 07

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How to open a 34C? and battery?
Message #1 Posted by Luca on 16 Jan 2002, 8:54 p.m.

My wife and I found an old 34C that she used before buying a15C. I would like to clean it and restore it to use.

The battery pack leaked and caused corrosion in the battery compartment. I will replace the batteries; what kind should I use - are normal NiCads fine, provided I get a good mechanical fit? We still have the original adaptor.

Also, I would like to open the calculator to check for internal corrosion. How do I do it? I unscrewed the two screws located at the top, but the case did not simply pop open: something at the base (the short edge close to the user and to the 0 . etc keys) keeps the two halfs together. Do I just need to pry it apart? I did not see screws behind the rubber feet.

If I do find corrosion, how do I best clean it? There was a thread on this some time ago, and I will see if I can find it... any suggestions are appreciated, anyway.

I will report on how it goes... Thanks,


Re: How to open a 34C? and battery?
Message #2 Posted by David Smith on 17 Jan 2002, 4:13 p.m.,
in response to message #1 by Luca

One think to watch out for on Spice machines that have corroded batteries (or even not) is the flat cable to the battery clips is VERY fragile. Battery leakage makes it MUCH more so. It is very easy to break a conductor or (even more likely) have it totally rip off. Then you have to trace the wiring and solder thin wires from the battery clips to the circuit board. Also those battery clips are also very prone to breaking. I would guess that at least 35 percent of existing Spice machines have a broken battery clip.

As far as opening the case goes, first try the squeeze technique. It works for me about 80 percent of the time. If not try placing the fron label end of the machine on a carpeted floor and pressing down with both thumbs in the battery compartment (the power squeeze technique). If all else fails it's time for the mighty yank technique.... CRAAAAK

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