Sony RMT-V259, Service Manual

Page: 70 / 93

7-2
2-1-6. Adjusting Sequence
Make the electrical adjustment in the following sequence.
2-3. SERVO SYSTEM ADJUSTMENT
2-3-1. RF Switching Position Adjustment
(MA-373 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: Pin
1
of CN262
CH2: Pin
2
of CN262
(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) During playback, connect MA-373 board CN262 pin
3
and
the pin
5
for about 1 second 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.
2-2. POWER SUPPLY ADJUSTMENTS
2-2-1. Power Supply Check
(SRV938EK BOARD)
Checking Method:
1) Confirm that each voltage meets its specified value.
2-2-2. +6 V Adjustment
(SRV938EK BOARD)
Mode REC or PB
Measuring Instrument Digital voltmeter
Measurement Point Pin
qf
of CN201
Adjusting Element VR251
Specified Value 5.9 ± 0.2 V
Power supply adjustment
Servo system adjustment
Audio system adjustment
Approx. 1 Vp-p
Approx. 5 Vp-p
V
enlargement
CH2
CH1
CH2
CH1
Vertical sync. signal
6.5
±
0.5 H
(416
±
32
µ
sec) PAL
(410
±
32
µ
sec) NTSC
Mode E-E
Measuring Instrument Digital voltmeter
MTR12 V check
Measurement Point Pin
5
,
6
of CN201
Specified Value 13.5 ±0.4 V
D6 V check
Measurement Point Pin
qf
of CN201
Specified Value 5.9 ± 0.2 V
+13 V check
Measurement Point Pin
qs
of CN201
Specified Value 13.6 ± 0.5 V
+38 V check
Measurement Point Pin
2
of CN202
Specified Value 35.0 ± 3.5 V
SW 5 Vcheck
Measurement Point Pin
qg
,
qh
of CN201
Specified Value 5.2 ± 0.2 V
+F, –F check
Measurement Point Pin
4
,
6
of CN202
Specified Value 2.9 V
–11 V check
Measurement Point Pin
3
of CN202
Specified Value –11.5 ± 1.0 V
+ 0.6
– 0.3