Heathkit IT-12, Assembly Manual

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( ) Slip the length of flat braid through the probe end and bend over as shown. Wrap a short length of bare wire around
the flat braid and the cable shield and solder. Cut off excess cable shield. Do not cut off braid.
( ) Solder an alligator clip to the other end of the braid.
( ) Slip the terminal board and switch into the probe body and mount the switch with the two small 4-40 screws.
( ) Push the black probe end into the end of the probe body, making sure that the flat braid is between the probe body and
the flat side of the probe end. Fasten the end with two small self tapping screws.
( ) Screw the probe tip into the red probe end, and remove the collar from the tip. Slip the red end into the probe body,
making sure the wire comes through the hole in the tip. Secure the end in the probe body with the two self tapping screws.
Wrap the wire around the probe tip and replace the collar.
( ) Remove the paper backing from the RF-AUDIOdecal, and place it on the probe body with the audio end towards the
tip.
( ) Assemble the red and black test leads as shown.
( ) Remove the 3/8 nuts from control Rl and switch Sl. Mount the
chassis to the panel using a nickel control washer between the panel
and the 3/8 control nuts.
( ) Feed the four remaining wires from the out-put transformer
through the chassis slot behind switch Sl. Connect the black wire to
lug 1 (Sl) of speaker switch S4.
( ) Connect a short length of bare wire be-tween lug 2 (Sl) of switch
S4 and lug 2 (NS) to terminal strip X.
( ) Connect one lead of a 68 K ohm resistor (blue-grey-orange) to
lug 2 (Sl) of noise switch S3. Connect the other lead to lug 1 (NS) of
terminal strip X.
( ) Connect the wire from lug 2 of condenser C7 to lug 1 (NS) of
switch S3.
( ) Connect the wire from pin 6 of V2 to lug 1 (S2) of switch S3.
( ) Connect the lead from lug 1 ol the oti-on switch to panel terminal H (NS).
( ) Connect the green wire from the output translormer to terminal H (S3).
( ) Connect the red transformer lead to terminal F (Sl). Connect the wire from pin 7 of socket V2 to terminal G (NS).