Panasonic Omnivision PV-9661, Service Manual

Page: 289 / 407

Fig. M8
6.2.2.5.4. AUDIO CONTROL HEAD
AZIMUTH ADJUSTMENT
Purpose: To adjust the position and height of the
Audio Control Head so that it meets the
tape tracks properly.
Symptom of
Misadjustment: If the position of the Audio Control Head
is not properly adjusted, the Audio S/N
Ratio is poor.
1. Connect the oscilloscope to the audio output jack on the
rear side of the deck.
2. Play back the 6kHz Monaural Audio portion of the alignment
tape.
3. Adjust Black Screw (C) on the Audio Control Head base so
that the output level is at maximum.
Fig. M9
4. Confirm the height of the Audio Control Head is proper. If
not, readjust Black Screws (A) and (B).
6.2.2.5.5. AUDIO CONTROL HEAD
HORIZONTAL POSITION
ADJUSTMENT
Purpose: To adjust the Horizontal Position of the
Audio Control Head.
Symptom of
Misadjustment: If the Horizontal Position of the Audio
Control Head is not properly adjusted, a
maximum envelope cannot be obtained at
the Neutral Position of the Tracking
Control Circuit.
1. Connect the oscilloscope to TP3002 on the Video Signal
Process Section of the Main C.B.A. Use TP6205 as a
trigger.
2. Place a jumper between TP6003 on the Video Signal
Process Section and +5V(TP6009) on the System Control
Section of the Main C.B.A. to defeat Auto Tracking.
3. Eject the tape and insert it again to access the Neutral
Tracking position.
4. Play back the alignment tape and confirm that the RF
envelope appears.
5. 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.
6. 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.
7. 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.
8. 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.
9. 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.
10. Tighten Black Screw (D).
(The Black Screw (D) should be in the approximate center
of the hole.)
11. Remove the jumper between TP6003 and +5V(TP6009).
Fig. M10
Note:
Old type of H-Position Adjustment Driver (VFK0136) can be
used for this adjustment.
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PV-9661 / PV-9662