Panasonic OmniVision PV-M1347, Service Manual

Page: 43 / 143

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5. A/C HEAD HORIZONTAL POSITION
ADJUSTMENT
Purpose:
To adjust the Horizontal Position of the A/C Head.
Symptom of Misadjustment:
If the Horizontal Position of the A/C Head is not properly
adjusted, a maximum envelope cannot be obtained at the
Neutral Position of the Tracking Control Circuit.
Place a jumper between TP6003 and +5V(TP6009) on the
System Control Section of the Main C.B.A. to defeat Auto
Tracking.
1. Eject the tape and insert it again to access the Neutral
Tracking position. Connect the oscilloscope to TP3002 on
the Video Signal Process Section of the Main C.B.A. Use
TP6205 as a trigger.
2. Play back the alignment tape and confirm that the RF
envelope appears.
3. If adjustment is required, loosen the Black Screw (D) and
tighten it lightly. Set the H-Position Adjustment Driver into
the Hole (A). Then slowly turn the fixture either clockwise or
counterclockwise so that the envelope is at maximum.
4. Before finding the center of the maximum period of the
envelope, rotate the fixture back and forth slightly to confirm
the limits on either side of the maximum period.
5. Push the Tracking Control Up Button (on the Remote
Control) several times (count the number of times pushed)
until the maximum envelope is reduced to 1/2.
6. Reset the tracking to the neutral position by ejecting the
tape and reinserting it. Push the Tracking Control Down
Button (on the Remote Control) several times (count the
number of times pushed) until the maximum envelope is
reduced to 1/2.
7. If the number of pushing is not the same, then loosen the
Black Screw (D) and set the H-Position Adjustment Driver
into the Hole (A) to find the center point. Then repeat the
above procedure to determine the center point.
8. Tighten Black Screw (D).
9. Remove the jumper between TP6003 and +5V(TP6009).
Fig. M11
Note:
Old type of H-Position Adjustment Driver (VFK0136) can
be used for this adjustment.
Black Screw (D)
Hole (A)