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[HP48GX] Testing repaired keyboard
08-01-2016, 12:00 PM
Post: #11
RE: [HP48GX] Testing repaired keyboard
Hi Mark,
I have checked and your are right:
Quote: the PCB to have a single ground plane that uses one or more twist ties as a return path to the batteries.

the only pad that isn't connected to the ground plane is that I marked in the pic as A.

Now I have twisted the tabs but I have anyway a bad connection between the PCB and flatpack keyboard. So I need to reopen the twist tabs :-( and I need to find something to put in place of the rubber. I took the measurements of the existing rubber and its section is about 3x4 mm. I noticed that the original rubber is flexible enough to be crushed but also stiff enough to push the flatpack against PCB and now I'm looking for something on the market that can be good for size and consistency.

I had another problem when I closed the unit: when I powered the unit almost the whole screen was switched on but I don't know why. (it could be dust or overpressed the PCB against the flatpack?)
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[HP48GX] Testing repaired keyboard - fnas - 07-21-2016, 09:29 AM
RE: [HP48GX] Testing repaired keyboard - fnas - 08-01-2016 12:00 PM

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