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HP Forum Archive 14

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Hp 15c keyboard
Message #1 Posted by j.serra on 8 June 2004, 5:09 p.m.

Hi all,

I've found recendly a 15c. It's in a very good condition but some of its keys have an excesive movement, I mean, if you shake the calc it sounds like a maraca.

Is there any solution for that ?

Thanks

      
Re: Hp 15c keyboard
Message #2 Posted by Raymond Del Tondo on 8 June 2004, 5:29 p.m.,
in response to message #1 by j.serra

Hi,

as long as they have the tactile feedback, I wouldn't care about the rattle. Do the keys all have the same straight travel way, and same angle when depressed?

Raymond

            
Re: Hp 15c keyboard
Message #3 Posted by JDH on 8 June 2004, 7:58 p.m.,
in response to message #2 by Raymond Del Tondo

Sounds like the calculator has been opened up in the past and not put together again properly. If your game you could open up the back of the calculator to confirm it.

                  
Re: Hp 15c keyboard
Message #4 Posted by Trent Moseley on 8 June 2004, 9:22 p.m.,
in response to message #3 by JDH

If it works don't fool with it!

      
Re: Hp 15c keyboard
Message #5 Posted by Randy on 8 June 2004, 10:39 p.m.,
in response to message #1 by j.serra

If you open it, you may find some of the heat stake mushroom heads have sheared off. The result is a loose circuit board, which makes keys in those areas loose and feel soft when pressed. Once they start to fail, it is like a zipper or a crack in plastics. The forces get transferred to the next rivet in line and then it fails, so on and so on. This is common on Voyagers that have been pounded heavily.

The best solution is to glue the loose areas with a drop of rubber toughened cyanoacrylate on each post that is missing the mushroom. Loctite 410 is good choice if you can get it. ** BE CAREFUL ** Too much and you'll glue a key in the up position!

      
Re: Hp 15c keyboard
Message #6 Posted by Karl Schneider on 8 June 2004, 11:14 p.m.,
in response to message #1 by j.serra

J.S. --

It's difficult to tell if the movement is truly "excessive" from the description. Is it that the keys rattle a bit when the calc is shaken, or that some keys travel excessively when pressed?

I have three Voyagers -- a 15C from 1983, a 16C from 1985, and a 12C from 1993. On the 15C and the 12C, the keys have a bit of freeplay in their "slots"; they rattle when shaken.

On the 16C, the keys stay firmly in place until pressed -- no rattling.

None of these show any sign of having been pounded, and they all work perfectly.

            
Re: Hp 15c keyboard
Message #7 Posted by j.serra on 10 June 2004, 6:57 a.m.,
in response to message #6 by Karl Schneider

First of all thanks for your answers.

The question is that nearly all the keys have some freeplay in their slots, but in the case of the ENTER is specialy high, is not a problem for to play with, the only thing that bother me is the long term durability.

I've opened the machine and the plastic welding are perfect so I assume that nobody has opened it before.

What about FixthatCalc, could be a solution?

                  
Re: Hp 15c keyboard
Message #8 Posted by Karl Schneider on 10 June 2004, 11:32 p.m.,
in response to message #7 by j.serra

J.S. --

Just to clarify: When I mentioned "free play", I referred mainly to side-to-side movement, not up-and-down movement, of the keys.

FixThatCalc.com (Randy Sloyer) does excellent work; I have used his services once and plan to do so again.

-- Karl S.


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