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For various reasons, conductive paths keyboard lose their ability to conduct electricity.
Damaged areas can be repaired.
Let us keyboard.
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We are looking for damaged areas and find the keyboard.
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Use a tester see that it is really damaged parts. Damaged in the photo look discolored. In this case, all six tracks is damaged.
Will restore the conductive adhesive. If it is dry, his "revive" a few drops of solvent and agitation. For agitation can bring any electrical means.
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The technology is simple: create a conductive adhesive on top of the damaged wiring. But in case you need to restore 5 tracks that are very close to do it is extremely difficult, not "drove" to the neighboring. Most, if not impossible without the use of special equipment.
Therefore, another method was used: paint the glue stain the entire affected area, then scratched raszdeliteli between tracks. Thus it was possible to restore four of the five tracks.
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But what of the fifth, it is also necessary. Let us assume it successfully recovered over four lanes. You can draw paint "bridge" over the ready, and after drying lacquer on the "bridge" to draw a path conductive adhesive. And you can stick a thin copper wiring.
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But the posting does not isolated, we cover the central part of the nail (the height of a capital letter 6 millimeters).
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We are waiting for the paint to dry up, but not completely, to avoid cracked varnish and glue on the posting on his new position. After glue it to the rest of the conductive paths.
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After drying, the tester check whether all paths goals and a short circuit between adjacent tracks and the one that is the "second floor".