Pioneer VSX-4000 Service Manual page 46

13.5 © ENHANCER DOES NOT WORK.
Enhancer does not
work. Defective
periphery of color
signal eliminating
circuit Q109
(2SC1740S) within AF
video assembly
(AWZ1097) or
Is enhancer VR at
center?
Check
respective DC
voltages to enhancer
circuit Q108 to Q115
within AF video
assembly
(AWZ1097).
13.6 SPLIT SCREEN DOES NOT WORK.
Split screen does
not work.
Does the control
signal synchronized
with the horizontal
signal emit at pin
(No.5 and No.13) of
switch IC (1C102:
TC4066) within the-
AF video assembly
(AWZ1097)?
Does the output (Pin
3) of timer circuit IC
(IC107: M5184}
emits?
Defective 3/6 and 4/6
of inverter IC (IC105).
Is the output (Pin 2:
horizontal
synchronizing signal)
of inverter IC (IC105:
TC4069) normai?
When the split screen
VR (VR102: 100k) is
13.7 FM(AM) DOES NOT RECEIVE.
FM (AM) does not
receive.
Does the TUNED IND
light up?
Does output of tuner
output (J1:L,R out)
within tuner assem-
bly (AWZ1093)
emit?
Defective periphery
of IC401 (AN7470P)
Are other functions
normal?
Defective signal
course from J1 of
tuner assembly to
function selection
1C510 (TC9163N) of
small signal assembly
(AWZ1094).
To pages 39.
13-2. Sound does not emit.
Does FM/AM
selection Tr Q405
and Q411 within the
tuner assembly
(AWZ1093) operate
normally?
Is tuning voltage
(Pin 73: VT.TP)
normal?
WVE-> Ciajele/e/t=1,¢)
Defective periphery
of IC403 (LM7001),
Q405 and 0411.
Defective periphery
of 1C403 (LM7001),
Q409 and 0410.
Defective 1C402
(LA12658)
Defective periphery
of Q120 (2SA1237)
within AF video
assembly and VR
102 (AWZ1097).
moved, does the
above-mentioned
duty of the control
signal alters smoothly
to about 10% to
90%?
Defective periphery
from Q117 to inverter
IC (1C105 1/6).
Defective switch IC
(1102).
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