DV-NC65H (serv.man13). Adjustment, replacement and assembly of mechanical units - Sharp DVD Service Manual (repair manual). Page 17

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.

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.

When the tape is below the helical lead.

When the tape is above the helical lead.