Sony RMT-V245A, Service Manual

Page: 28 / 55

7-2
2-1-6. Adjusting Sequence
Make the electrical adjustment in the following sequence.
Checking power supply
Servo system adjustment
Audio system adjustment
2-3. SERVO SYSTEM Adjustment
2-3-1. RF Switching Position Adjustment
(MA-323 Board)
Purpose:
Adjust the interval between A ch and B ch of tape playback out-
put.
Improve the interchangeability with other tapes and sets.
When it is out of order, the interval appears on the screen, the
screen is disturbed.
Mode PB
Signal Alignment tape SP mode
color bar
Measurement Point CH1: VIDEO LINE OUT
CH2: Pin
2
of CN501
(RF SWP)
Measuring Instrument Oscilloscope
Specified Value 6.5 ± 0.5 H (416 ± 32 µsec)
PAL
6.5 ± 0.5 H (410 ± 32 µsec)
NTSC
Adjusting Method:
1) Connect MA-323 board JS140 to the GND for about 1 secont
to activate the RF switching position adjustment mode.
2) Check appear “A P” on FL display.
3) Using the c and – buttons, adjust to 6.5 ± 0.5 H.
4) Press the pause button.
Fig. 7-2-3.
Mode E-E
Measuring Instrument Digital voltmeter
–10 V check
Measurement Point Pin
9
of CN600
Specified Value –10.3 ±0.8 V
+6 V check
Measurement Point Pin
7
,
8
of CN600
Specified Value 5.9 ± 0.2 V
+13 V check
Measurement Point Pin
2
,
3
of CN600
Specified Value 13.3 ± 0.5 V
+35 V check
Measurement Point Pin
1
of CN600
Specified Value 38.0 ± 3.0 V
2-2. POWER SUPPLY ADJUSTMENT
2-2-1. Power Supply Check
HS-921SF/921SF1 BOARD,
SR-708/718 BOARD
Checking Method:
1) Confirm that each voltage meets its specified value.
2-2-2. +6 V Adjustment
HS-921SF/921SF1 BOARD,
SR-708/718 BOARD
Approx. 1 Vp-p
Approx. 5 Vp-p
V
enargement
CH2
CH1
CH2
CH1
Vertical sync. signal
6.5
±
0.5 H
(416
±
32
µ
sec) PAL
(410
±
32
µ
sec) NTSC
Mode REC or PB
Measuring Instrument Digital voltmeter
Measurement Point Pin
7
,
8
of CN201
Adjusting Element RV201 (HS-921SF/921SF1
BOARD)
VR201 (SR-708/718
BOARD)
Specified Value 5.9 ± 0.2 V
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