Tektronix 1L20, Инструкция по эксплуатации

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M aintenance— Type 1L20
in Step 4, and the cables. See Fig. 4-3 and Table 4-3 for
the correct hook-up.
Table 4 -3
PIN
Square Pin C onnector
W IR IN G COLOR CODE
A
W hite— no tracer
B
W hite— brown tracer (large wire)
C
W hite— yellow tracer
D
W hite— green tracer
E W hite— black & red tracers
F W hite— brown-black traces (+ 1 0 0 V)
G
W hite— black-brown tracers (+ 1 0 V)
H
Tan— brown & green tracers (— 150 V)
1
No connection
J
No connection
Remounting the Phase Lock Assembly
1. Remove the three phase-lock control nuts, V620, and
the cables (if they were replaced in Step 8 of the procedure
given above).
2. Slide the phase-lock chassis back into its cover plate.
3. Replace the six Phillips head screws fastening the phase-
lock chassis to the phase-lock cover.
4. Remount the phase-lock assembly on the main chassis.
Guide the handle o f the INT 1 MHz REF FREQ switch into
place with a small screwdriver.
5. Replace the nuts securing the front panel controls and
the rear tab.
IMPORTANT
Be sure the correct nut is used to secure the INT
1 MHz REF FREQ sw itch. Because o f the thread
d ifference, use o f the w ro n g nut w ill cause b in d ­
ing and dam age th e threads.
6. Reconnect the cabling as shown in Fig. 4-3 and Table
4-3.
7. Replace the FINE FREQ control knob. Be sure it is
indexed correctly— see step 7q o f the calibration procedure.
Component Replacement
Ceramic Strips. Unsolder all connections, then use a %
inch diameter by 3 inch long plastic or hardwood dowel and
a small (2 to 4 oz.) mallet to knock the stud pins (see Fig. 4-4)
out of the chassis. Place one end o f the dowel on the end of
the stud pin protruding through the chassis. Rap the opposite
end of the dowel smartly with the mallet. When both studs
of the strip have been loosened in this fashion, the strip is
removed as a unit. The spacers w ill probably come out with
4 -4
Fig. 4 -3 . Wiring and cable connections to Phase-Lock assembly.