Sony SLV-7700KME, Service Manual

Page: 99 / 135

7-5
2-4-4. RF PLL Free-run Frequency Check (BD-21 Board)
Signal Reference disc
Measurement
TP PLCK
point
Measuring
Frequency counter
instrument
Specified
4.3218 MHz
value
[Check Method]
1)
Connect frequency counter to TP (PLCK) with lead wire.
2) Turned Power switch on.
3) Put the disc (YEDS-18) in to play the number five track.
Confirm that reading on frequency counter is 4.3218 MHz.
2-4-5. Clock Adjustment (CD-169 Board)
Measurement
IC305 pin
*ª
point
Measuring
Frequency counter
instrument
Adjustment
CT301
element
Specified
13500000 ± 40 Hz
value
[Adjusting Method]
1)
Connect the frequency counter to check point of the CD-169
board.
2) Adjust CT501 of the CD-169 board so that the frequency
counter read 13.5 MHz ± 40 Hz at STOP condition.
2-5. SERVO SYSTEM ADJUSTMENT
2-5-1. RF Switching Position Adjustment (MA-303 Board)
[Adjustment Object]
To adjust the link of the Ach and Bch of the tape playback outputs.
If this specification is not satisfied, the noise will increase and
cracking sounds will be produced.
Mode Playback
Signal Alignment tape : Color bar portion
Measurement CH1 : LINE-1 OUT VIDEO terminal
point CH2 : CN502 pin
3
(RF SWP)(RP-233 board)
Measuring
Oscilloscope
instrument
Adjustment
RV202
element
Specified
6.5 ± 0.5H (416 ± 32
µ
sec)
value
[Adjusting Method]
1)
Set TRACKING switch (Remote commander) to MANUAL.
(“Auto tracking” display will disappear on the display window
indicator.)
2) Press the tracking buttons $ and 4 and adjust the tracking
position to the center.
3) Adjust to 6.5 ± 0.5H (413 ± 32
µ
sec) using RV202.
Fig. 7-2-10.
Fig. 7-2-11.
Normal tracking
TV screen
Moves to the right when the 4 button in pressed
and to the left when the $ button is pressed.
Approx. 1Vp-p
Approx. 5Vp-p
V
CH1
CH2
CH1
CH2
CN502 pin
3
(RF SWP)
Enlargemant
Vertical sync. signal
6.5
±
0.5H
(416
±
32
µ
sec.)