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2. A/V, SECAM, VPS Circuit Diagram WAVEFORM & VOLTAGE SHEET
_ IC301 Oscilloscope Waveform
X301 is defective.
PB COLOR Signal disappear.
IC301 Pin 20 IC301 Pins 38,32,31 IC301 Pin 28 IC301 Pin 7
PB mode Video in PB/REC mode REC mode
500mvp-p 1Vp-p 4.2Vp-p 1.4Vp-p
13 12
IC301 Pin 6 IC301 Pin 29 IC301 Pin 41 IC301 Pin 64
11 8
REC mode PB mode PB mode PB mode
2.2Vp-p 2.1Vp-p 400mVp-p 600mVp-p
16
7
2
IC301 Pin 23 IC301 Pin 24 IC301 Pins 71 , 72 IC301 Pins 51, 52,54
PB/REC mode PB/REC mode REC mode PB mode
5Vp-p 5Vp-p 340mVp-p 300mVp-p
IC301 Pin 93 is defective.
9
Audio Tracking is failed. 1
2
IC301 Pin 63 IC301 Pin 11 IC301 Pin 10 IC301 Pin 43
PB mode PB mode PB mode PB mode
10 3 6 600mVp-p 3.2Vp-p 1.8Vp-p 400mVp-p
5 4 15 14
IC301 Pin 10 is defective. _ IC301 Voltage Sheet _ IC201 Voltage Sheet _ TR Voltage Sheet
PB COLOR Signal disappear. E C B E C B
PIN PB REC PIN PB REC PIN PB REC PIN PB REC PIN PB REC PB mode REC mode
1 2.44 2.42 21 2.41 2.52 41 2.93 2.92 61 3.43 3.43 81 0 0 1 2.239 2.238 2.216 13 3.574 3.565 3.567 E C B E C B
2 2.44 2.42 22 0 0 42 3.16 3.14 62 3.31 3.32 82 0.03 0.04 2 4.794 4.823 4.731 14 4.442 4.438 4.396 Q301 1.213 3.930 1.864 1.783 3.348 2.435
3 2.46 2.44 23 4.48 4.52 43 3.02 2.05 63 5 5 83 0 0 3 3.099 3.098 3.066 15 1.946 1.923 0.093 Q302 1.548 5.158 2.191 1.813 5.147 2.452
4 2.45 2.35 24 4.19 4.23 44 0 0 64 5 5 84 0.03 0.03 4 4.264 4.260 4.216 16 3.199 3.2 3.176 Q303 2.161 0 1.499 2.147 0 1.494
5 0.09 0.88 25 1.69 1.69 45 2.34 2.33 65 2.03 2.03 85 0.03 0.03 5 5.196 5.192 5.137 17 5.150 5.138 5.120 Q304 1.217 5.061 1.835 1.216 5.039 1.824
Q308, Q309, Q310
6 2.46 2.34 26 0.05 0.06 46 1.46 1.44 66 2.66 2.67 86 0 0 6 4.315 4.163 4.231 18 2.798 2.857 2.701 Q305 2.383 0 1.705 2.420 0 1.749
are defective.
7 2.46 2.34 27 0.34 0.34 47 9.13 9.12 67 3.87 3.86 87 4.87 4.80 7 4.652 4.554 4.467 19 2.215 2.938 2.203 Q306 1.222 0 0.545 1.221 0 0.557
No mono Audio Signal 8 0.001 0.001 0.001 20 0.002 0.002 0.002
8 0 0 28 0.34 0.34 48 1.94 1.96 68 0 0 88 1.83 3.97 Q307 5.258 0.280 5.176 5.186 3.301 4.352
in PB MODE.
Q301, 302 are defective. Q305 is defective. 9 0 0 29 1.78 1.84 49 0.85 0.85 69 0.80 1.27 89 0 0 9 0.360 0.358 0.359 21 2.615 2.613 2.603 Q308 0 0 0.744 15.624 0 -21.49
FL301, Q309, Q311 are defective.
PB Screen is bad. EE, PB Screen doesn't appear. D301 or IC301 Pin30 is defective. 10 0.93 0.93 30 1.10 4.57 50 0 0 70 1.98 2.92 90 1.83 3.95 10 0.048 0.050 0.059 22 2.780 2.802 2.701 Q309 0 0 0.720 -5.69 0 -21.77
Normal Audio signal is not recorded. 11 3.262 3.261 3.236 23 3.387 3.324 3.356
REC is failded. 11 1.68 1.68 31 2.97 2.94 51 1.83 1.82 71 2.52 2.51 91 1.83 3.98 Q310 5.256 5.180 4.583 5.189 -21.64 5.148
IC301 Pin 23, 24 are defective. 12 4.98 2.60 32 - 2.3 52 2.71 2.62 72 3.37 1.73 92 0.02 1.55 12 1.794 1.813 1.803 24 2.549 2.554 2.538 Q311 1.224 3.923 1.872 0.271 3.190 0.688
PB and Recording is failed. 13 1.49 1.52 33 1.45 1.37 53 0 0 73 3.8 3.17 93 2.17 0.01 Q3A1 0 5.251 0 1.258 5.179 1.756
(IC301 doesn't operate.) 14 1.68 1.38 34 1.81 1.79 54 2.62 2.62 74 1.55 0.01 94 0 2.01 Q201 1.313 5.135 1.924 0.625 5.116 0.092
REC Y+C PB Y+C REC SECAM COLOR PB AUDIO(MONO) 15 2.34 2.32 35 3.25 3.22 55 4.91 4.91 75 4.96 4.94 95 0 0 Q202 1.314 5.135 1.237 0.624 5.120 1.219
16 5.01 5.02 36 1.82 1.95 56 0.56 0.57 76 2.43 2.41 96 2.29 2.38 Q203 0 1.924 0.016 0 0.092 5.111
REC Y PB Y PB SECAM COLOR REC AUDIO WAVE FORM 17 3.08 0.15 37 4.79 4.79 57 3.44 3.44 77 0.01 0.14 97 0 0
REC C PB C 18 1.98 2.45 38 1.81 2.25 58 5.00 5.00 78 2.42 2.42 98 2.43 2.41
19 1.18 2.45 39 4.10 4.10 59 3.36 3.37 79 2.46 2.45 99 5.08 4.28
20 3.01 3.05 40 5.00 5.00 60 3.31 3.31 80 2.43 2.23 100 2.43 2.60
3-32 3-33 3-34