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CIRCUIT DIAGRAMS * IC101 Voltage Sheet
PB 16.1 4.0
* IC102 Voltage Sheet
PB 4.0 0.0

1. Power, Tuner, NICAM/A2 Circuit Diagram REC 16.3
5
4.6 REC 4.0
4
0.0



No 5.3VA and 5VG, 5VT. D109, C120 are defective. IC101 IC102
Switching dead.
D106 is defective. No 14VA, 12VA are 12VT. 1 1
IC101 is defective.
PB 309 0.0 0.0 PB 4.9 3.9
Power dead. No power. REC 309 0.0 0.0 REC 4.9 4.0
BD101, R101 are defective. D102 is defective.




Power dead.
F101 is defective. No 5.2VT.
Q152 is defective.




Power dead.
IC102, IC103 are defective.
_ TR Voltage Sheet
Emitter Collector Base
PB REC PB REC PB REC
Q151 11.9 11.8 14.8 15.0 12.5 12.4
Q152 9.4 9.3 11.8 11.6 10.0 9.9
Q153 11.8 11.7 14.8 15.0 12.4 12.3
Q154 -27.3 -27.9 -27.3 -27.8 -26.6 -27.0
Q155 5.3 5.3 5.2 5.3 0.0 0.0
Q156 -16.1 -16.5 -16.0 -16.4 -15.4 -15.7
Q157 5.3 5.3 5.2 5.2 0.0 0.0
Q158 35.6 36.0 35.3 35.7 35.0 35.4
Q159 5.3 5.3 5.2 5.2 4.5 4.5
Q160 0.0 0.0 0.0 0.0 5.0 5.0
Q161 0.0 0.0 0.1 0.0 5.0 5.0
Q162 5.3 5.3 5.2 5.2 4.5 4.5
Q164 5.3 5.3 5.3 5.3 4.6 4.6
Q165 0.0 0.0 10.0 10.0 0.0 0.0


NOTE :
EE MODE(VIDEO) 1. Shaded( ) parts are critical for safety. Replace only
* IC103 Voltage Sheet
Emitter Collector Base
EE/PB MODE (VIDEO) NOTES) Symbol denotes AC ground.
NOTE)
NOTE)
Warning
Parts that are shaded are critical
with specified part number.
2. Voltages are DC-measured with a digital voltmeter PB REC PB REC PB REC
NOTE) With respect to risk of fire or
TU MODE (AUDIO) NOTES) Symbol denotes DC chassis ground.
NOTE) electricial shock.
during TUNER mode. IC103 2.5 2.5 0.0 0.0 3.9 3.9




3-30 3-31
2. A/V 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




11 8
IC301 Pin 6 IC301 Pin 29 IC301 Pin 41 IC301 Pin 64
IC301 Pin 93 is defective.
Audio Tracking is failed.
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



9
1
2




IC301 Pin 63 IC301 Pin 11 IC301 Pin 10 IC301 Pin 43
3 6
PB mode PB mode PB mode PB mode
10
5 15
600mVp-p 3.2Vp-p 1.8Vp-p 400mVp-p
4 14




IC301 Pin 10 is defective.
_ IC301 Voltage Sheet _ TR Voltage Sheet
PB COLOR Signal disappear.
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 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 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 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 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 Q304 1.217 5.061 1.835 1.216 5.039 1.824
6 2.46 2.34 26 0.05 0.06 46 1.46 1.44 66 2.66 2.67 86 0 0 Q305 2.383 0 1.705 2.420 0 1.749
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 Q306 1.222 0 0.545 1.221 0 0.557
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
Q308, Q309, Q310
are defective. 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 Q308 0 0 0.744 15.624 0 -21.49
FL301, Q307, Q311 are defective. EE, PB Screen doesn't appear. 10 0.93 0.93 30 1.10 4.57 50 0 0 70 1.98 2.92 90 1.83 3.95 Q309 0 0 0.720 -5.69 0 -21.77
No mono Audio Signal PB Screen is bad.
in PB MODE. Normal Audio signal is not recorded. 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 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.) D301 or IC301 Pin30 is defective. 14 1.68 1.38 34 1.81 1.79 54 2.62 2.62 74 1.55 0.01 94 0 2.01
REC Y+C PB Y+C 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
WAVEFORM REC is failded.
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
REC Y PB Y REC AUDIO
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
* IC501 Waveform Photographs
3. System Circuit Diagram

Reset is defective.
LD Motor will not operate.
Set dead. PB PG will not operate. VCR dead.
IC502, ZD501 are defective.
IC504 is defective. VR501 is defective. IC505 is defective.

IC501 Pin 24 IC501 Pin 27 IC501 Pin 31 IC501 Pin 32
1V/5mS 1V/2mS 1V/10mS 1V/10mS
REC/PB modes QUE/REV modes REC mode REC mode
(V.H/SW) (D.V-SYNC) (CTL+) (CTL-)




IC501 Pin 38 IC501 Pin 39 IC501 Pin 40 IC501 Pin 43
1V/1mS 1V/10uS 1V/1mS 100mV/10uS
REC/PB mode REC/PB modes REC/PB modes EE/PB modes
(DFG) (DPG) (CFG) (V-IN)




IC501 Pin 45 IC501 Pin 54
500MV/10uS 1V/20uS
EE/PB modes EE/PB modes
(V-OUT) (C-SYNC)
1

2 10
5 6 7 8 9
3 4




_ System IC Voltage Sheet _ SYSTEM IC Voltage Sheet
Emitter Collector Base