LG TCH-800, Service Manual

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- 2-3 -
(3) Initial reading is not carried out (with disc)
DISC loading?
YES
NO
NO
NO
NO
NO
NO
NO
NO
Is IC201 pin21 input waveform
normal?
IC201
pin21
open close
YES
Does laser light?
CDP PCB: CON1 pin14(LD)
YES
YES
YES YES
Is signal output at tracking
output IC501 Pin 53 (CDP PCB)?
Does IC201 Pin25(LKFS) GFS
as figure?
Disc initial reading damaged or
defective.
Disc defective.
Is rotation normal?
Is there any irregularity in
frequency?
YES
Is RF signal normal without
dropout?
NO
Check voltage in the power
supply circuitry .
Q505, R506, IC201 pin39, pin87
CDP PCB: IC301.
NO
Leaf SW contact defective.
Connector defective.
Pattern short.
NO
(A)
(B)
Does disc motor rotate?
Is RF wave output?
RF
Is tracking servo operating?
Is the lower envelope of RF
waveform flat? Is signal output at TEO?
Is signal output at IC101
Pin50 (CDP PCB)?
IC501(CDP PCB) defective.
Pattern defective.
Connector defective.
Pick-up defective.
IC502 (CDP PCB) defective.
NO
IC201(CDP PCB) defective.