4-3
4-3 ELECTRICAL ADJUSTMENT INSTRUCTIONS
NOTE:
1.Electrical adjustments are required after replacing
circuit components and certain mechanical parts.
It is important to do these adjustments only after
all repairs and replacements have been com-
pleted. Also, do not attempt these adjustments
unless the proper equipment is available.
2.To perform these alignment / confirmation proce-
dures, make sure that the tracking control is set in
the center position: Press either "CHANNEL
L5??
" or
"CHANNEL
K
" button on the front panel first, then
the "VCR-PLAY" button on the front panel.
4-3-1 Test Equipment Required
1.Oscilloscope: Dual-trace with 10:1 probe,
V-Range: 0.001~50V/Div.,
F-Range: DC~AC-20MHz
2.Alignment Tape (MH-1)
4-3-2 Head Switching Position
Adjustment
Purpose:
To determine the Head Switching position during
playback.
Symptom of Misadjustment:
May cause Head Switching noise or vertical jitter
in the picture.
Reference Notes:
Playback the Alignment tape and adjust VR501 so that
the V-sync front edge of the CH1 video output wave-
form is at the 6.5H
±
1H(412.7
µ
s
±
63.5
µ
s) delayed posi-
tion from the rising edge of the CH2 head switching
pulse waveform.
Test point
Adj.Point
Mode
Input
TP751(V-OUT)
TP302(RF-SW)
GND
VR501
(Switching Point)
(MAIN CBA)
PLAY
(SP)
-----
Tape
Measurement
Equipment
Spec.
MH-1
Oscilloscope
6.5H
±
1H
(412.7
µ
s
±
63.5
µ
s)
Connections of Measurement Equipment
Oscilloscope
Main CBA
TP751
CH1 CH2
Trig. (+)
GND
TP302
Figure 1
EXT. Syncronize Trigger Point
1.0H
CH1
CH2
Switching Pulse
V-Sync
0.5H
6.5H
±
1H (412.7
µ
s
±
63.5
µ
s)
Содержание DV-PF35U
Страница 79: ...S 5 S 4 Main 1 8 Schematic Diagram ...
Страница 81: ...S 7 S 6 Main 3 8 Schematic Diagram ...
Страница 82: ...S 8 S 7 Main 4 8 Schematic Diagram ...
Страница 83: ...S 9 S 8 Main 5 8 Schematic Diagram ...
Страница 84: ...S 10 S 9 Main 6 8 DVD Open Close Schematic Diagram ...
Страница 86: ...S 12 S 11 Main 8 8 Schematic Diagram ...
Страница 87: ...S 13 S 12 DVD Main 1 3 Schematic Diagram 1 NOTE Either IC461 or IC462 is used for DVD MAIN CBA ...
Страница 88: ...S 14 S 13 DVD Main 2 3 Schematic Diagram ...
Страница 90: ...S 16 S 15 DVD Main 3 3 Schematic Diagram ...
Страница 102: ...DV PF35U No 0508E TK Digital Media Division Yokohama ...