Text preview for : system circuit diagram.pdf part of LG system circuit diagram LG VCR bc490w system circuit diagram.pdf
Back to : system circuit diagram.pd | Home
* IC501 Waveform Photographs
3. System Circuit Diagram
VCR dead.
Reset is defective. IC505 is defective.
LD Motor will not operate. Set dead. PB PG will not operate.
IC502, ZD501 are defective. IC504 is defective. VR501 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
_ IC502 Voltage Sheet _ System IC Voltage Sheet _ SYSTEM IC Voltage Sheet
PB 0.4 0.8 12.19 12.19 2.16 Emitter Collector Base