
The switches are not that great really. Scratchy, bind if you press too far off center and use graphite contacts.
Looking at the force curve you can clearly see the effect of the two spring system.





















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The "lens on a chip" is probably a EPROM. Typically these have a label covering them when programmed, and you can remove it and blast the chip with UV light to reset the chip and re-program. I would cover it to preserve the programming if you expect to use it or dump the ROM at some later time.