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HP Forum Archive 17

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48GX button is stuck
Message #1 Posted by Natan Samuels on 3 Apr 2007, 12:37 p.m.

My professor and I were crunching some numbers, he hit the "+" key, and it got stuck in the down position. Does anyone know how to remedy this situation?

      
Re: 48GX button is stuck
Message #2 Posted by Dave Boyd on 3 Apr 2007, 2:13 p.m.,
in response to message #1 by Natan Samuels

Quote:
My professor and I were crunching some numbers, he hit the "+" key, and it got stuck in the down position. Does anyone know how to remedy this situation?

Since I lack anything useful to say, I'll just note, in passing, that this is why it's better to "massage" the numbers than to "crunch" them.

Ask any statistician.

            
Re: 48GX button is stuck
Message #3 Posted by Natan Samuels on 3 Apr 2007, 11:12 p.m.,
in response to message #2 by Dave Boyd

Quote:

Since I lack anything useful to say, I'll just note, in passing, that this is why it's better to "massage" the numbers than to "crunch" them.

Ask any statistician.


Yeah, that was a pretty useless comment, Dave.

      
Re: 48GX button is stuck
Message #4 Posted by Jeff O. on 4 Apr 2007, 8:02 a.m.,
in response to message #1 by Natan Samuels

Not sure if this will be much more useful than Dave's comment, but, since none of the experts have chimed in, I'll tell you what I know.
The hp48 keyboard is formed as bunch of domes in a plastic sheet. When you press a key, the dome below it collapes and a conductive coating on the bottom of the dome makes contact with a circuit below. It sounds like you have a permanently collapsed dome, which is most likely not repairable. If you want to try, a detailed description of how to open the 48 can be found by clicking on this link. For repair tips and a description of keyboard construction, click here.
Or maybe the key is just stuck down with some gunk, in which case rinsing and/or ultrasonic cleaning with distilled water has been discussed here a few times in the past, search the archives.

      
Re: 48GX button is stuck
Message #5 Posted by Massimo Gnerucci (Italy) on 4 Apr 2007, 1:49 p.m.,
in response to message #1 by Natan Samuels

A couple of months back I got a 48GX which had an ON key stuck down and I was not able to move it whatsoever.
Later I noticed that the metal bezel around this key was a little loose and bent up so I managed to push it down while playing with the key and then it was finally free.
The glue under the lower left corner of the bezel was probably gone... Since the + key is in the lower right corner you could check for a similar problem.

Just my 2

Greetings,
Massimo

            
Re: 48GX button is stuck
Message #6 Posted by Ron on 4 Apr 2007, 4:16 p.m.,
in response to message #5 by Massimo Gnerucci (Italy)

I have seen this, too. Straightened up the mtal, and freed the key.

            
Re: 48GX button is stuck
Message #7 Posted by Natan Samuels on 6 Apr 2007, 1:35 p.m.,
in response to message #5 by Massimo Gnerucci (Italy)

Thanks so much, Jeff, Massimo, and Ron. You gave a lot of great tips and I'll probably try out some of the less-complicated ones this weekend. Hopefully, just the metal is off-center!

Natan

      
Re: 48GX button is stuck
Message #8 Posted by Natan Samuels on 6 Apr 2007, 3:57 p.m.,
in response to message #1 by Natan Samuels

The problem was indeed the metal bezel holding down the bottom of the "+" button. I'm trying to think exactly how that could have happened. Maybe the calc got shifted around in a funny way in my bookbag (even though I always keeping it in the case - with the quick guide inside facing the keys for extra protection). Here's what's bothering me: I lifted up the lower right corner of the bezel to unstick the key - which worked. However, replacing the bezel sticks the key again. Must I therefore always leave the corner sticking up? Mind you, it sticks up enough only to be level with the plastic shell, but that condition seems like it might lend itelf to some other problem down the road. Nonetheless, I'm happy to have my calc workinging again without spending any money, and a very small amount of time!

By the way: This is a minute point, but my calc is a 48SX, not a GX.

            
Re: 48GX button is stuck
Message #9 Posted by Randy on 6 Apr 2007, 4:23 p.m.,
in response to message #8 by Natan Samuels

Trying to pull the metal back down generally ends in disaster. I've found you can carefully shave the metal away at the bottom to enlarge the opening. A new #11 X-Acto blade works well but you must do this with the plate lifted away from the calculator and be *very* careful not to allow the blade to go past the metal and hit the key. If you hit the key hinge at the bottom (which is obscured by the plate), the + key will become loose and eventually you'll end up with a dead, non-repairable calculator. You also need to keep the shavings out of the keyboard. It takes a steady hand.

The usual cause for the damage is from the calculator having been dropped on the corner. SX's and GX's are for almost all purposes, identical, at least mechanically.


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