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HP Forum Archive 14

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32s keyboard flex problem
Message #1 Posted by ned on 14 Oct 2004, 12:09 a.m.

I tend to inherit broken things other people think I can fix, as is the case with my 'new' 32s: The middle keys esp. the "[sst] 4 5 6 [multiply]" row don't register unless the upper chassis is pushed down. The whole chassis has a permanent bow to it, bowed up across the short section, bowed down across it's length. I read the archived posts by Mr's Brogger & Duell regarding opening up pioneers, and the opening was a success. 'Unflexing' the upper plastic seems a bit difficult without cutting all the plastic welds, which would really screw things up. Anyone have a method of fixing this problem? I seem to remember reading about Pioneer series keyboard flex before but couldn't find the post.

AtDhVaAnNkCsE Ned

      
Re: 32s keyboard flex problem
Message #2 Posted by Randy on 14 Oct 2004, 8:47 a.m.,
in response to message #1 by ned

The bow in the plate is common in older Pioneers and is not the problem. The problem is the small foam pad under the keyboard connector - it is either out of position or it has lost is spring force, perhaps a combination of both. Shimming the pad with several layers of flexible tape is usually all that is required.

            
Re: 32s keyboard flex problem
Message #3 Posted by bill platt on 14 Oct 2004, 9:06 a.m.,
in response to message #2 by Randy

Hi Randy,

In order to shim, do you need to take the chassis all the way apart?

Does this rule--shimming to bring a keyboard back to life-- also apply to the 48 series?

Best regards,

Bill

                  
Re: 32s keyboard flex problem
Message #4 Posted by Randy on 14 Oct 2004, 1:01 p.m.,
in response to message #3 by bill platt

I'm not sure what you mean by "taking the chassis all the way apart". You only have to remove the logic board from the frame. Anything beyond that and it's tough to get it back together.

The 48's have identical issues/fixes.

                        
Re: 32s keyboard flex problem
Message #5 Posted by ned on 14 Oct 2004, 3:22 p.m.,
in response to message #4 by Randy

Yes, turning the metal keeper tabs back parallel with the slots should free the circuit board. See: http://www.hpmuseum.org/guest/brogpion.htm thanks for the tip about the pad. I'll take the leap tonite and undo the tabs.

-Ned

                              
problem sovled
Message #6 Posted by ned on 20 Oct 2004, 9:53 p.m.,
in response to message #5 by ned

okay upon removing the rear chassis and the pcb, I saw that the problem (with most pioneers maybe) is that 2 hooks, or teeth on the front chassis became detached from the metal plate. In this case, the front chassis was allowed to flex out, causing lack of contact at the keyboard connector. This is just below the lcd, where the keyboard connects to the pcb via the printed mylar. Shimming the foam pad might work also, but hooking the teeth back to the metal solves the problem. Poor design IMHO. The front chassis provides no stiffness, the metal plate should have been channelled for stiffness.

-Ned


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