Broadcasting system: B/G,H
Color system: PAL color bar
(2) Signal level
Input electric field: 40 ± 3dBµ (IF AGC full gain), P/S = 10 dB
(3) Other conditions
CCIR IF (Input electric field: terminated with 75-ohm resistance)
Power supply: Vcc1-1 = 5.0 ± 0.05 [V]
• Adjustment
Monitor video detection signal (CP238) via a low-pass filter of 100 kHz cutoff frequency and adjust
LLD coil T200 so that its DC level is minimum (waveform’s amplitude is maximum).
(Reference: C= 1500 pF, R = 1 Kohm)
• Confirmation
There should be no waveform distortion (erroneous synchronization, etc.), under sensitivity (video
detector output level is abnormally small, etc.).
• Block diagram
Signal
generator
IF signal
L-PCB
Adjust to minimize the DC level.
Stabilizer
VCC1-1
Detector OUT
Low-Pass Filter
DC IN
Oscilloscope
— 4 —
3.Free running frequency adjustment
• Conditions
(1) Signal
No signal (PAL standard signal should be applied only at synchronous check)
(2) Signal level
Input electric field only at synchronous check: 70 dBµ (terminated with 75-ohm resistance),
P/S = 10 dB
(3) Other conditions
CCIR IF input only at synchronous check (input electric field with 75-ohm termination).
Connect SYF terminal (CP729) and VCC2-7.
Power supply: Vcc1-1 = 5.0 ± 0.05 [V]
Room temperature: 20 ± 10 [°C]
• Adjustment
Monitoring HDB (CP305) with a frequency counter, adjust VR700 so that the frequency is 15.625 ±
0.1 [kHz].
• Caution
(1) Disconnect the wire between SYF terminal and VCC2-7.
Applying IF signal make sure that synchronization is normal on the display.
(2) Use input signal pattern conforming CCIR standard.
• Block diagram
Signal
generator
VCC1-1
Stabilizer
4.Contrast adjustment
• Conditions
(1) Signal
Broadcasting system: B/G,H
Color system: PAL color bar
(2) Signal level
Input electric field: 70 dBµ (terminated with 75-ohm resistance), P/S = 10 dB
(3) Other conditions
CCIR IF input (input electric field should be terminated with 75-ohm resistance).
Apply voltage of Vcc1-1 = 5.0 ± 0.05 [V]
L-PCB
SYF
HD
VCC2-7
Frequency
Counter
• Adjustment
Connect color terminal (CP320) to GND (CP300) so that screen becomes black and white. Adjust
contrast pot VR300 so that the voltage between pedestal level and white level of B signal (CP740) is
0.80 ± 0.05 [Vp-p].
— 5 —
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