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HP Forum Archive 14

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USA Made Hp 12c with "Popping" Keys
Message #1 Posted by Neil on 19 Feb 2005, 5:36 a.m.

Hi,

I just received a mint condition USA made Hp-12c. I was surprised to notice that quite a few of the keys make a popping sound just like on most of my Indonesian-made pioneer calcs.

I have a couple of other voyagers as well as a quite a few pioneers, and I always thought that the characteristic of the earlier USA, Singapore, Malaysian, Brazil etc. made models was that the keys do not "pop" when you press them. This is true for all my earlier calcs. All my Indonesian-made calcs "pop" except for my HP 32sii.

I've read on the forum that the Indonesian-made calcs tend to be more prone to keyboard problems. So does this mean that for the HP 12c calc I just received, the keyboard quality might not be as good as a "non-popping" voyager? Perhaps due to bad storage conditions leading to deterioration with age, or because it was a factory second? Has anybody else got such a "popping" USA made voyager?

My initial thought when I received this HP-12c was that it could be a Chinese-made HP-12c, but no, it takes the 3 button cells, and it has not been tampered in any way.

      
Re: USA Made Hp 12c with "Popping" Keys
Message #2 Posted by will on 19 Feb 2005, 6:19 a.m.,
in response to message #1 by Neil

i´ve got a brand new hp12c (made in usa, in VERY mint condition, box included ) with no "poping" keys..in fact its keyboard is as good as it was expected to be...i have other voyager calc (11c bought 10 years ago from a co-worker) with loose keys (since i got it) and used with excelent results. this have worked as well as the first does, in fact i prefer my 11c...

            
Re: USA Made Hp 12c with "Popping" Keys
Message #3 Posted by Nelson M. Sicuro (Brazil) on 19 Feb 2005, 10:06 a.m.,
in response to message #2 by will

If the calculator has a very used keyboard, the rubber membrane below the keys may develop "holes" where the keys press the steel domes. This also let the keys a little lower than normal.

This caused the "rattle" of the keys on one 12C I had.

Anoter cause is in the assembly line when the case isn't well pressed with the "hot tool(?)" that makes the melting of the plastic pins, leaving a very small space between the plastic keys and the steel domes.

Best regards,

Nelson

      
Re: USA Made Hp 12c with "Popping" Keys
Message #4 Posted by Larry Corrado on 20 Feb 2005, 10:02 a.m.,
in response to message #1 by Neil

Neil:

I bought a used 12C a few years ago that had a key that sort of popped: it required extra pressure, and then suddenly broke loose. However, I noticed that I only had to "pop" the key once, and then it was ok for that session. If I didn't use the machine for a few days (hours?), I would have to break that key free again with a single press, and then it was fine.

I assumed the problem was due to a sticky substance (eg, a spilled soft drink) getting under the key and then drying out, leaving a dry sticky residue that wouldn't stick unless left for a while. I haven't tried to fix the problem.

Of course, you say your machine is "mint," so maybe this is less likely.

Anyway, a possibility...

Larry


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