Zenith C32V23 - 32" Flat-Screen Integrated HDTV, Руководство по обслуживанию

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PV154 - 923-03497
3-21
AB - SERVICING
SERVICING
No Analog OSD (micro section)
Go to HD In Source
and press Menu Key (any
Menu must be
displayed)
No Yes
Check 27Mhz signal is present
at pins 34 and 35 of IC6000
No Yes
Check Fast Blank signal is
present (at pin 61 IC6000)
The problem in the OSD
Oscillator, check CRY6002,
RM6039, CM6037, CM6038
No Yes
Check RGB’s (pins 62,63 and 64 IC 6000) Check RM6068, RM2201
Analog OSD is ok
No Yes
Check RM2281, RM2284, RM2285
and then verify ther are RGB’s at the
output of the CRT Driver CXA2150
(ICM2200 at pins 62, 63 and 64)
Reset TV
RF INPUT ANT 1 (2)
CHECK 0 (9) , 9 & 0
VOLTS AT PINS 1, 2,
& 3 OF CNRFSW
RESPECTIVELY.
NO CHECK +9VRS AT LX3837 AND
9VVRS LINE.
CHECK 4.5(0.0)VOLTS AT PIN
30 OF CNP201A.
YES
CHECK 5V AT PINS 4 & 16
AND SCL & SDA AT PINS
4 & 5 OF WT1200.
CHECK +5VTNA AT LX3825 AND
+5VTNA LINE. CHECK IIC BUS
LINES.
NO
ANALOG RF SIGNAL
DIGITAL RF SIGNAL
YES
CHECK COMPOSITE
VIDEO SIGNAL AT
PIN 15 OF WT1200
YES
NO
CHECK AGC (Pin 2 of WT1200)
VOLTAGE VARIATION WITH/
WITHOUT RF INPUT SIGNAL.
CHECK TUNING VOLTAGE (Pin
3 of WT1200) VARIATION WHEN
SELECTING DIFFERENT CHA
-
NNELS.CHECK BY CONNEC-
TING THE RF SIGNAL DIRECTLY
TO TUNER INPUT (Omit RF
Switch).
CHECK COMPOSITE VI-
DEO SIGNAL AT POSITI-
VE LEAD OF C2903 NO
CHECK PROPER ASSEMBLY/BIA
SING OF Q1206 AND C2903
YES
IF STILL NO SUCCESS
PLEASE REFER TO THE
VIDEO TROUBLESHOO
TING SECTION.
CHECK FOR DIGITAL SIGNAL
1.1Vpp at TP1206.
(scope =20mS horizontal sweep)
NO
YES
CHECK ADJUST OF R1242.
CHECK SAW FILTERS, Q1202,
IC1203 ASSEMBLY AND BIA-
SING
CHECK L1206 ADJUSTMENT.
TURN IT SLOWSLY UNTILL
DIGITAL VIDEO APPEARS
IN THE SCREEN
NO
CHECK D.C. OSC. FREQ. TO BE
76MHZ +/-50KHZ.
CHECK DIGITAL BOARD.
END
END
YES
No Video (RF section)