Reference Pll Center Frequency Adjustment; Reference Cf Detection Adjustment - Panasonic DVCPRO AJ-D455P Service Manual

4-2. Reference PLL Center
Frequency Adjustment
BOARD
V OUT (F2)
TP TP600 (VCO)
ADJ. VC600 (FREQ ADJ)
TAPE -----
INPUT REF VIDEO IN
Analog Composite Signal
(75% Color Bar with 7.5% Set-Up)
MODE -----
M. EQ Oscilloscope
DC Level: 0 ± 0.1VDC
SPEC.
1. Adjust VC600 so that the DC voltage at TP600 is
in the specification.
<Note>
When the hand and so on approach too much near
VC600 in adjustment, the DC voltage sometimes
shifts.
TP600
0 ± 0.1VDC
4-3. Reference CF Detection
Adjustment
BOARD
V OUT (F2)
TP Composite Signal CF OUT,
TP704 (CF)
TP702 (CF_TP2), TP703 (CF_TP1)
ADJ. VR560 (SCH DET)
TAPE -----
INPUT REF VIDEO IN
Analog Composite Signal
(75% Color Bar with 7.5% Set-Up)
MODE -----
M. EQ Oscilloscope
See Figure, A=B ± 5nsec
SPEC.
1. Connect the oscilloscope CH1 to the CF output of
composite signal generator and CH2 to TP704.
2. Adjust VR560 so that the phase is synchronized
between CF pulses and TP704 as shown in
figure.
And confirm that the "SCH_ON (C-1)" LED on the
board is turned on.
Trigger
CF OUT
TP704
3. Connect the oscilloscope CH1 to TP702 and CH2
to TP703.
4. Expand (delay) the rising edge of TP702.
5. Slowly and slightly rotate VR560 so that the rising
edge of TP702 is positioned at the center of cross
point between A and B of waveform at TP703.
Trigger
TP702
TP703
TP702
TP703
ELE-12
The waveform will be
Changed depend on
Expansion
A B
A=B ± 5nsec