Switching Position Adj; Play Tracking Confirm And Adj - Sony SVT-RA40 Service Manual

3-1-3. Switching Position Adj.

Measuring Point Measuring Equipment
TP101(VIDEO Oscilloscope
OUT terminal)
TP183 (SW-P)
Adj. Condition
REC button, TRACKING
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.
REC button
Start of play
back display
ON
OFF
withi
withi
2 sec.
10 sec.
Fig. 2-1-2
3-2
Adj. Condition
PLAY (8 H) mode
Alignment tape
VHJ-0007
Adj. Condition
6.5 H ±0.5 H
more
then
adjusting
0.5
period 10 sec.
sec.
3-1-4. 24 H Play Tracking Confirm and Adj.
Measuring Point Measuring Equipment
Picture of Color bar generator
monitor TV (Monoscope pattern
signal) Monitor TV
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.
T = 6.5 H ±0.5 H
1 H
Fall
RF.SW.PULSE
Fig. 2-1-3
Adj. Condition
Self-recording
(8 H) mode
24 H PLAY mode
Blank tape
Adj. Condition
—
0.5 H
Front edge of
vertical sync signal
SVT-RA40/RA168