Sony SVT-RA168, Service Manual

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3-2
SVT-RA40/RA168
3-1-3. Switching Position Adj.
Measuring Point Measuring Equipment Adj. Condition
TP101(VIDEO Oscilloscope PLAY (8 H) mode
OUT terminal) Alignment tape
TP183 (SW-P) VHJ-0007
Adj. Condition Adj. Condition
REC button, TRACKING 6.5 H
±
0.5 H
buttons, EJECT button
1. Play back the alignment tape. Press the TRACKING
buttons ( + ) and ( _ ) simultaneously. (TRACKING
center position)
2. Press the REC button three times within 10 seconds
after the display is shown. All three presses must be
carried out within 3 seconds. For the third time, press
the REC button more than 0.5 seconds as shown in
Fig. 2-1-2.
3. The automatic adjustment mode is set, the numerals of
Indicator display “P 0 : 00” changes automatically and
the unit stops at the point the adjustment value be-
comes approx. 6.5 H.
4. In the same adjustment mode, trigger at the edge of the
RF SW pulse, and check that the front edge of the V
sync signal from the fall edge of the RF SW pulse is
delayed by 6.5 H
±
0.5 H as shown in Fig. 2-1-3. If it is
not 6.5 H
±
0.5 H, manually perform fine adjustments
for the TRACKING buttons ( + ) or ( _ ) to satisfy the
specification.
5. After completing adjustments, press the EJECT button
(more than 1 second) and check the Indicator shows “P
– –” at this time.
n
Repeat steps 1 to 4 if the adjustment takes more then 20
seconds.
3-1-4. 24 H Play Tracking Confirm and Adj.
Measuring Point Measuring Equipment Adj. Condition
Picture of Color bar generator Self-recording
monitor TV (Monoscope pattern (8 H) mode
signal) Monitor TV 24 H PLAY mode
Blank tape
Adj. Condition Adj. Condition
TRACKING buttons —
REC button
1. Insert blank VHS cassette tape and record monoscope
pattern on the 8 H mode.
2. Play back the self-recorded tape and then set the VCR
in the 24 H mode.
3. Use the front tracking adjustment button to fine-tune to
the optimum position so that the positions of noise on
the monitor screen at the tracking center are vertically
symmetrical. Then press the REC button more than 1
second to enter this position as the new tracking
center. The indication displays “P – –” for approxi-
mately 1 second.
4. If vertical shaking occurs at the tracking center, read
just by pushing the TRACKING buttons (no more than
3 times), then enter this new tracking position as the
tracking center.
Start of play
REC button
ON
OFF
withi
withi
more
adjusting
back display
10 sec.
2 sec.
then
0.5
sec.
period 10 sec.
0.5 H 1 H
Front edge of
RF.SW.PULSE
Fall
vertical sync signal
T = 6.5 H
±
0.5 H
Fig. 2-1-2 Fig. 2-1-3