Sharp DV-NC65H, Service Manual

Page: 36 / 113

36
DV-NC65H/S
DV-NC70H
Notes:
When the A/C head X value adjustment is performed, be
sure to perform at first X value rough adjustment (refer to
8-
19 , 3-
2
).
4. A/C head X value adjustment
1
Fix A/C head arm screws
1
and
2
tentatively by the
method described in " 8-17 Replacement 3".
2
Playback the alignment tape (VROCPSV), and
shortcircuit between TP803 and TP802 on VCR
Operatin PWB. As a result the auto-tracking is auto-
matically cancelled, so that the X value adjustment
mode is set.
3
Move the A/C head with the X value adjustment gear
driver by the method shown in
Figure 8-34 , and
adjust the A/C head so as to get the maximum ATR
signal waveform. (Note: At this time adjust so as to
get the maximum ATR signal waveform nearest the
A/C head position which has been set in case of X
value rough adjustment as stated in
8-19 , 3-
2
.)
4
Adjust the playback switching point (Refer to the
electric adjustment method.)
5
Playback the self-picture-recorded tape, and check
the flatness of ATR signal waveform and sound.
Figure 8-32.
1
Take-up side Supply side Take-up side
Adjustment
Supply side
Supply side guide roller
rotated in clockwise
direction (lowers guide
roller) to flatten
ATR signal. Take-up side guide roller
rotated in clockwise
direction (lowers guide
roller) to flatten
ATR signal. Supply side guide roller
rotated in counterclock-
wise direction (raises
guide roller) to make the
tape float above the helical
lead. The supply
side guide roller is then
rotated in the clockwise
direction to flatten the
ATR signal.
Take-up side guide roller
rotated in counterclock-
wise direction (raises
guide roller) to make the
tape float above the
helical lead. The take-up
side guide roller is then
rotated in the clockwise
direction to flatten the
ATR signal.
Figure 8-31.
When the tape is below the helical lead. When the tape is above the helical lead.