Heathkit IT-12, Assembly Manual

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( ) Connect the blue transformer wire to terminal G (S3).
( ) Feed the probe cable through grommet I and connect the inner conductor to lug 1 (S3) of terminal strip X. Connect
the cable shield to lug 2 (S4)
( ) Twist the green and brown leads from the eye tube
socket and connect the green lead to lug 3 (S3) of terminal
strip Q. Connect the brown lead to lug 2 (S3).
( ) Connect the red lead to lug 1 (S3) of conden-ser C7.
( ) Twist the orange and blue leads together and connect the
orange lead to pin 4 (S2) of sock-et VI. Connect the blue
lead to pin 5 (S2). This completes the T-4 wiring. Check
over connections and make sure that all have been soldered.
( ) Install the 12AX7, VI and the 12CA5, V2 tubes.
( ) Mount the eye tube by sliding the two sheet metal screws
into the slots in the chassis and tightening down, and then
push the tube forward against the panel.
( ) Install an 8-32 x 1/4" setscrew in each of the two knobs.
( ) Install the level control and off-on switch knobs. Position
the pointers so they line up with panel markings.
( ) Install red binding post caps on the speaker and the C. T.
post.
( ) Install black caps on the B+ and P post.
( ) Slightly spread the open end of the binding posts with a
phillips screwdriver after the binding post caps have been
screwed on. Tap the screwdriver lightly. This will keep the
binding post caps from falling off.
( ) Install the four rubber feet on the bottom of the cabinet.
( ) Install the handle using the two #10 sheet metal screws.
NOTE: The blue and white identification label shows the Model Number and Productions Series Number of your kit.
Refer to these numbers in any communications with the Heath Company; this assures you that you will receive the most
complete and up-to-date information in return.
( ) Carefully peel away the backing paper from the blue and white identification label. Then press the label onto the rear
of the cabinet.
Before installing the instrument in the cabinet, using 6-32 screws, these preliminary tests should be performed. Turn on the instrument
and advance the level control. Turn the speaker switch on and the noise switch off. After a few seconds the 1629 eye tube should light
green, thus indi-cating that the B+ and filament circuits are functioning properly. The shadow position of the tube may be adjusted in
the panel by rotating the tube. A loud hum should be heard when the probe tip is touched with the hand.
( ) If operation is normal, install the cabinet with 6-32 screws. If the Signal Tracer did not operate properly, refer to the In
Case Of Difficulty section of the manual.
IN CASE OF DIFFICULTY
If the Signal Tracer failed to operate in the preliminary test, again check over all connections for unsoldered or poor
joints. Using the pictorial diagrams, trace each lead with a red pencil to make sure each one is connected properly. Make
sure that no component leads are shorted to each other or to the chassis. Trace through the instrument by touching the grid