1-7-1
H9300EA
ELECTRICAL ADJUSTMENT INSTRUCTIONS
General Note: "CBA" is an abbreviation for
"Circuit Board Assembly."
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 "
L5??
" or "
K
" button
on the remote control unit first, then the "PLAY"
button (Front Panel only).
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 point 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(412.7
µ
s) delayed position from the
rising edge of the CH2 head switching pulse wave-
form.
Test point
Adj.Point
Mode
Input
TP751(V-OUT)
TP504(RF-SW)
GND
VR501
(Switching Point)
(MAIN CBA)
PLAY
(SP)
-----
Tape
Measurement
Equipment
Spec.
FL6A
Oscilloscope
6.5H
±
1H
(412.7
µ
s
±
60
µ
s)
Connections of Measurement Equipment
Figure 1
Oscilloscope
Main CBA
TP751
CH1 CH2
Trig. (+)
GND
TP502
EXT. Syncronize Trigger Point
1.0H
CH1
CH2
Switching Pulse
6.5H
V-Sync
0.5H
Summary of Contents for DBVR-2700
Page 32: ...1 10 6 1 10 7 1 10 8 H9308SCM2 Main 2 7 Schematic Diagram VCR Section...
Page 33: ...Main 3 7 Schematic Diagram VCR Section 1 10 9 1 10 10 1 10 11 H9308SCM3...
Page 34: ...Main 4 7 Schematic Diagram VCR Section 1 10 12 1 10 13 1 10 14 H9308SCM4...
Page 35: ...1 10 15 1 10 16 Main 5 7 Schematic Diagram VCR Section H9308SCM5...
Page 36: ...1 10 17 1 10 18 H9308SCM6 Main 6 7 Schematic Diagram VCR Section...
Page 37: ...1 10 19 1 10 20 H9308SCM7 Main 7 7 Schematic Diagram VCR Section...
Page 40: ...1 10 25 1 10 26 H9308SCAFV AFV Schematic Diagram VCR Section...
Page 43: ...1 10 31 1 10 32 BH9311F01013 B Function CBA Top View Function CBA Bottom View...
Page 46: ...1 10 38 1 10 39 1 10 40 BH9311F01013 A Main CBA Bottom View...
Page 47: ...1 10 41 1 10 42 1 10 43 H9308SCD1 DVD Main 1 4 Schematic Diagram DVD Section...
Page 48: ...1 10 44 1 10 45 1 10 46 H9308SCD2 DVD Main 2 4 Schematic Diagram DVD Section...
Page 49: ...1 10 47 1 10 48 1 10 49 H9308SCD3 DVD Main 3 4 Schematic Diagram DVD Section...
Page 50: ...1 10 50 1 10 51 1 10 52 H9308SCD4 DVD Main 4 4 Schematic Diagram DVD Section...
Page 72: ...2 4 6 DUALPALDA S 12 19 Cap Belt Fig DM11 Fig DM12 20 C 1 21...
Page 99: ...DBVR 2700 H9308BD...