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HP Forum Archive 19

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48G keyboard weirdness
Message #1 Posted by Lincoln on 8 Jan 2010, 5:50 p.m.

Hi, Got a 48G on eBay recently. Worked fine for a little while, but now the enter key is flaky, and in a strange way. Sometimes it won't work at all, sometimes it works, and a lot of times it will work if I keep it pressed down for anywhere between 1 and 10 seconds. Unfortunately, most of the time that it works it will count as multiple presses, usually two.

Any hints?

      
Re: 48G keyboard weirdness
Message #2 Posted by Han on 8 Jan 2010, 7:17 p.m.,
in response to message #1 by Lincoln

Does pressing down on the bezel between the screen and the first row of menu keys help? If so, you may simply have an air-gap between the PCB and the keyboard connectors.

http://www.math.uiuc.edu/~handuong/hp48/repair/

            
Re: 48G keyboard weirdness
Message #3 Posted by Lincoln on 8 Jan 2010, 7:44 p.m.,
in response to message #2 by Han

I tried that and it doesn't seem to make any difference. It's the occasional delayed activation that confuses me.

                  
Re: 48G keyboard weirdness
Message #4 Posted by Vieira, Luiz C. (Brazil) on 9 Jan 2010, 8:17 a.m.,
in response to message #3 by Lincoln

Hi, Lincoln;

because the key has a 'motion irregularity', it seems to me it is a mechanical problem. The delayed activation may also be related to this as well.

Anyway, to remove any chance of software causes, can you save all of your data and clear calculator memory? You can also hardware reset the calculator by using the small hole in the back of it. Then you can try the key again and see what happens.

Not too much of a help, I know...

Success!

Luiz (Brazil)

Edited: 9 Jan 2010, 8:18 a.m.

                        
Re: 48G keyboard weirdness
Message #5 Posted by reth on 10 Jan 2010, 3:39 a.m.,
in response to message #4 by Vieira, Luiz C. (Brazil)

Quote:
... it seems to me it is a mechanical problem.
which one should expect from a 20 years old calculator even though I've got 5 of them working perfectly so far.
                              
Re: 48G keyboard weirdness
Message #6 Posted by Vieira, Luiz C. (Brazil) on 10 Jan 2010, 3:09 p.m.,
in response to message #5 by reth

Hi;

I have a 48SX, two 48G+ and two HP49G. All working fine... What the f... do we know, ahn?

Cheers.

Luiz (Brazil)

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