Sony TRINITRON KV-VF21M40 Service Manual page 87

X'tal OSC CHECK
Mode PB
Signal Alignment tape, Stair step
Measurement Point MA10 board Q823 emitter(NTSC)
IC802 %ªpin(PAL)
Measurement Equipment Oscilloscope
Specified Value 500 200mVp-p
Check: 1)Confirm the frequency is 3.579545MHz 82Hz(NTSC), and
4.433619MHz 100Hz(PAL).
2)Confirm the waveform amplitude is 500 200mVp-p.
3.579545MHz
4.433619MHz
Fig.3-3
SYNC AGC CHECK
Mode E-E
Signal Color bar
Measurement Point MA10 board Q830 emitter
Measurement Equipment Oscilloscope
Specified Value 1.0 0.1Vp-p
Check: Confirm the waveform amplitude is 1.0 0.1Vp-p.
Fig.3-4
500 200mVp-p
82Hz (NTSC)
100Hz (PAL)
1.0 0.1Vp-p
CARRIER DEVIATION CHECK
Mode
Signal
Measurement Point
Measurement Equipment
Specified Value
Check: Confirm f
-f =1.00 0.08MHz
2 1
Confirm f =3.40 0.13MHz(NTSC), and
1
3.80 0.13MHz(PAL)
f
1
WHITE/DARK CLIP CHECK
Mode
Signal
Measurement Point
Measurement Equipment
Specified Value
Preparation: Add 3.3k resistor between IC802 $™pin and GND.
Check: Taking the height from sync to white level as 100%, check
white clip and dark clip.
– 99 –
E-E
Color bar
MA10 board IC802 !•pin
Spectrum Analyzer
f -f =1.00 0.08MHz
2 1
f
2
Fig.3-5
E-E
Color bar
MA10 board IC802 #¶pin
Oscilloscope
190 20%(White), 55 20%(Dark)
White clip
100%
Dark clip
Fig.3-6