Sony DNW-A100 Maintenance Manual page 479

If the output waveform is extremely abnormal
condition as shown in Fig.1 after replacing the
upper drum assembly, perform the upper drum
replacement again.
. Upper drum assembly replacement
(Refer to Section 5-2.)
10. F. FWD and REW Mode
(1) Press the PLAY button and play back the
SR2-1/P (00:00 to 15:00).
(2) Put the unit into the F. FWD mode and check
that the RF waveform satisfies specifications
6 and 7.
(3) Put the unit into the REW mode and check
that the RF waveform satisfies specifications
6 and 7.
If specifications 6 and 7 are not satisfied,
perform the adjustment (at the Tape Ap-
proaching Side or Tape Leaving Side) in
steps 12 and later.
DNW-A100/A50/A45
DNW-A100P/A50P/A45P
<Fig. 1>
. Abnormal waveform (For example)
A
B
D
Video Tracking Check (PLAY)
<SS-63 board, side A>
A B C D E F
S100
. Alignment tape : SR2-1/SR2-1P (00:00 to 15:00)
(Tracking VR : Not effective)
A
B
B
Spec. 6 : 100 > 70% (Drum entrance side)
x
A
C
100 > 70% (Drum exit side)
x
A
. Alignment tape : SR2-1/SR2-1P (00:00 to 15:00)
(Tracking VR : Not effective)
Spec. 7 : No waveform lacking exists.
Video Tracking Check (F. FWD, REW)
7-1-3. Video Tracking Check and Adjustment
C
E
G H J K L M N
RV100(Tracking VR)
A
C
P R
1
2
7-19