A time ago I acquired interesting scientific calculator SHARP EL-9000 to my collection.
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| SHARP EL-9000 |
But as I expected the flipping keyboard did not work at all. The reason was broken connections on the flex PCB where it is being bent. I tried to fix it with the conductive glue but it didn't work.
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| Broken connections |
So I decided to recreate the whole flex PCB. I removed it from the aluminium board.
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Keyboard flex PCB
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Then I scanned it and used as background in the KiCad to be able to create original traces. The Chinese PCB manufacturers offer relatively cheap flex PCB services so I sent them data of finished PCB.
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| "Digitalizing" the flex |
And this is the result. I was very satisfied with it
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| New flex arrived |
So I installed the new flex to the calculator and tested its functionality.
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| Flex installed to the keyboard |
The keyboard works perfectly. Now I am also able to use the printer CE-50P compatible with this calculator. Before the fix it wasn't possible because to start printing you have to press OPTION button which is located on the flipping keyboard.
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| And the keyboard works |
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| Now I can also use a printer |
