Sony DNW-A100 Maintenance Manual page 478

7-1-3. Video Tracking Check and Adjustment
9. PLAY Mode
(1) Connect the oscilloscope.
CH-1: TP106/SS-63 board
(AB EVEN ENV signal)
TRIG: TP325/SS-63 board (SS GOP signal)
Oscilloscope setting:
CH-1: 1 V/DIV
TRIG: 5 V/DIV
TIME: 5 ms/DIV
(2) Play back the SR2-1/P (00:00 to 15:00).
(3) Push S100 switch on the SS-63 board more
than 1 sec. so that the tracking VR becomes
to be effective.
(4) Turn the tracking VR so that the output level
of RF envelope waveform is maximized.
(5) Turn RV100 on the SS-63 board clockwise so
that the center portion of the RF envelope
waveform makes 80% of the maximum
output level.
(6) At the state of step (5), check that the RF
envelope waveform satisfies specification 4.
n
If the level fluctuates, read the average level.
(7) If the level fluctuates, turn RV100 on the SS-
63 board so that the output level in the center
portion of the RF envelope waveform is
maximum, and check that the fluctuation
amounts satisfy specification 5.
If specifications 4 and 5 are not satisfied,
perform the adjustment (at the Drum En-
trance Side or the Drum Exit Side) in steps 12
and later.
– Continued on the next page. –
7-18
<SS-63 board, side A>
A B C D E F
TP106
TP325 S100
. Alignment tape : SR2-1/SR2-1P (00:00 to 15:00)
<Head-to-tape contact>
A
B
A = RF max x 0.8
Spec.4: B
100 > 70%
x
A
C
100 > 70%
x
A
Output levels (B and C) at the drum
entrance side and exit side are more
than 70% of the center level(A).
<Fluctuation>
b
D = Average maximum level at waveform center
a
100 < 20%
Spec.5:
x
D
b
100 < 20%
x
D
c
100 < 20%
x
D
Fluctuation amounts (a, b, c) at the drum center
portion, entrance side and exit side are less
than 20% of the average maximum level (D).
G H J K L M N
RV100(Tracking VR)
RF max
C
a
RF max
c
D
DNW-A100/A50/A45
DNW-A100P/A50P/A45P
P R
1
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