7-2
2-3.
SERVO SYSTEM ADJUSTMENT
2-3-1.
RF Switching Position Adjustment
(MA-377 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
3
of CN202
(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-377 board JS401 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.
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
2-1-6.
Adjusting Sequence
Make the electrical adjustment in the following sequence.
Mode
E-E
Measuring Instrument
Digital voltmeter
+F, –F check
Measurement Point
Pin
qf
(+F), Pin
qh
(–F) of CN102
Specified Value
2.5 ± 0.4 V
–13 V check
Measurement Point
Pin
qk
of CN102
Specified Value
–11.75 ± 1.25 V
+6 V check
Measurement Point
Pin
3
,
4
of CN102
Specified Value
5.9 ± 0.2 V
+13 V check
Measurement Point
Pin
5
,
6
of CN102
Specified Value
13.8 ± 1.2 V
+38 V check
Measurement Point
Pin
1
,
2
of CN102
Specified Value
Max 40 V
2-2.
POWER SUPPLY ADJUSTMENT
2-2-1.
Power Supply Check
(PSM17-501 BOARD)
Checking Method:
1) Confirm that each voltage meets its specified value.
Power supply adjustment
Servo system adjustment
Audio system
adjustment
Tuner system
adjustment
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