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HP Forum Archive 15

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34c hard detents
Message #1 Posted by Hal on 21 Dec 2005, 2:08 a.m.

Hi folks.
Recently acquired my first spice, a nice 34c. In using it, I've noticed that the key detents are quite stiff (to the point that my finger started getting tired!). In fact, a couple keys even emit a sharp snapping sound when depressed (although this sound softens a bit after working the key a few times). The keys all function perfectly though. I guess HP envisioned ham fisted, heavy fingered operators when designing this machine. Is this characteristic of all spice models?
Thanks and best regards, Hal

      
Re: 34c hard detents
Message #2 Posted by Karl Schneider on 21 Dec 2005, 3:29 a.m.,
in response to message #1 by Hal

Hal --

I'd surmise that you have the original design (serial # beginning with 22 or lower) with plastic snap-ring detents and the unsoldered keyboard clamped on a steel plate. These snap rings are quite stiff and allow long key travel.

The 1982 redesign featured metal-dome detents on a properly-soldered keyboard without steel backing plate. The calc is lighter; there is less key travel and less effort; and, the circuitry is more reliable.

-- KS

            
Re: 34c hard detents
Message #3 Posted by Hal on 21 Dec 2005, 4:00 a.m.,
in response to message #2 by Karl Schneider

Yes indeed, the SN starts with 20 (made in Singapore), and it surely is heavy. Sometimes I lose a segment in the display also, but a slight twist on the case brings it back.
May have to acquire a redesigned unit just to see the difference. Thanks, Hal

      
Snapping Keys
Message #4 Posted by Larry Corrado, USA (Wisc) on 21 Dec 2005, 8:17 p.m.,
in response to message #1 by Hal

I have an HP-12C I got three years ago, used (s/n 3215xxxxxx). It works fine, but the "f" key snaps if I haven't used it recently (ie, in the last five seconds.) It seems to be both a tactile (touch) and audible snap.

It seems that the snap gets stronger the longer it (the "f" key") has been unused. My guess is that there is something sticky under the faceplate causing the problem. I haven't had the machine apart.

Have others noticed things like this?

larry

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