Hardware Hacking 23
Twist together the hot wire from the Piezo Disk and the inner wire from the
shielded cable. Solder them together. Twist together the ground wire from the
Piezo disk and the shield from the shielded cable. Solder them together. Wrap
both joints separately with a bit of electrical tape so that they cannot short against
each other.
Strip the free end of the shield cable as in step #5: 1” outer insulation, twist
shield, 1/2” inner insulation, twist conductor, tin the wires.
Unscrew the plug you are using to connect the contact mike to your
amplifier/recorder. Pass the barrel back over the shielded wire toward the disk
so that the threaded portion faces the freshly tinned end. Unscrewing the barrel
of the plug should have revealed two connector tabs: the shorter one connects to
the “tip” of the plug and the longer one connects to the “sleeve.”
Solder the inner conductor of the shielded wire to the tip of the plug and the
shield to the sleeve. Sometimes there are small holes in the connector tabs that
you can hook your wire onto, to hold it in place before soldering. Otherwise you
will have to tin the tabs and hold each wire against its respective tab while
soldering -- a job for three hands, a vise or a steady buddy.