1-7-1
E9G02EA
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 [PROG.
L
] or
[PROG
.
K
] button on the front panel first, then the
[PLAY] (VCR) button on the front panel.
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 (FL6A)
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 (416
µ
s
±
64
µ
s) delayed position
from the rising edge of the CH2 head switching pulse
waveform.
Test point
Adj.Point
Mode
Input
J236(JK1-V-OUT)
TP504(RF-SW)
GND
VR501
(Switching Point)
(MAIN CBA)
PLAY
(SP)
-----
Tape
Measurement
Equipment
Spec.
FL6A
Oscilloscope
6.5H
±
1H
(416
µ
s
±
64
µ
s)
Connections of Measurement Equipment
Oscilloscope
Main CBA
J236
CH1 CH2
Trig. (+)
GND
TP504
Figure 1
EXT. Syncronize Trigger Point
CH1
CH2
1.0H
0.5H
V-Sync
Switching Pulse
6.5H
±
1H (416
µ
s
±
64
µ
s)
Summary of Contents for DRVR-B778S
Page 17: ...1 6 5 E9G01DC Fig D10 20 Deck Pedestal 21 Front Bracket R S 19 S 19 S 19 S 19 S 20...
Page 56: ...1 13 3 E9G10SCM1 Main 1 9 Schematic Diagram VCR Section...
Page 58: ...1 13 5 E9G10SCM3 Main 3 9 Schematic Diagram VCR Section...
Page 59: ...1 13 6 E9G10SCM4 Main 4 9 Schematic Diagram VCR Section...
Page 60: ...1 13 7 E9G10SCM5 Main 5 9 Schematic Diagram VCR Section...
Page 61: ...1 13 8 E9G10SCM6 Main 6 9 Front Jack Schematic Diagram VCR Section...
Page 62: ...1 13 9 E9G10SCM7 Main 7 9 Schematic Diagram VCR Section...
Page 63: ...1 13 10 E9G10SCM8 Main 8 9 Schematic Diagram VCR Section...
Page 64: ...1 13 11 E9G10SCM9 Main 9 9 Schematic Diagram VCR Section...
Page 66: ...1 13 13 E9G10SCRJ Rear Jack Schematic Diagram VCR Section...
Page 67: ...1 13 14 E9G10SCAFV AFV Schematic Diagram VCR Section...
Page 87: ...1 18 2 E9G01PEX Packing X4 S2 S2 S3 S2 A14 S1 S5 S5 S2 X9 X3 S9 X2 X1 X31 X43 X22 X20 S10...
Page 104: ...DRVR B778S E9G10BD 2007 07 23...
