Sharp 21G-FX10L, Руководство по обслуживанию

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21G-FX10L
5 – 6
PIF ADJUSTMENT CHECKING
NO ADJUSTMENT POINT ADJUSTMENT CONDITION/PROCEDURE
WAVEFORM OR OTHERS
1 RF-AGC (1) Receive the "US 10 CH HALF Color Bar" signal.
* for Auto ADJ
TAKE OVER POINT
Signal Strength: 56 ± 1dBμV (75 ohm open) 1)Receive "NTSC COLOUR BAR" signal
ADJUSTMENT (2) Connect the oscilloscope to JA402 (Tuner's AGC Terminal) as shown in
signal strength : 56 ± 1 dBμV (75 ohm open).
(I2C BUS CONTROL) figure 3-1. 1) Go to service mode.
OSCILLOSCOPE 2) Go to service data V09 , press R/C to operate
(AUTO & MANUAL ADJ)
"Auto-AGC" key and confirm the OK display
on the screen
3) If appear red display with NG sign, increase data some
step and please repeat step 2.
BIAS BOX
4) Proceed step 4 & 5 in manual mode.
TV SET
Bias Box : about 4.5V
Fig. 3-1
(3) Call
V09
in service mode. Adjust the V09 bus data to obtain the Tuner
output pin drop
0.1V
below maximum voltage.
(4) Change the antenna input signal to 63 ~ 67dBμV, and make sure there
is no noise.
(5)Turn up the input signal to 90 ~ 95 dBμV to be sure that there is no cross
modulation beat.
FOCUS ADJUSTMENT
NO ADJUSTMENT POINT ADJUSTMENT CONDITION / PROCEDURE WAVEFORM OR REMARKS
1 FOCUS (1) Receive US4 CH LION HEAD Signal (NTSC 60 Hz).
(2) Press RESET to set Picture NORMAL condition.
(3) Adjust the focus control to get the best focusing.
ADJUSTMENT PRECAUTION : Make sure TV Set is in "NORMAL CONDITION" before switch to Service Mode for Adjustment.
Focusing Point (middle
of center and edge of
monoscope pattern)
+
-
+
-
JA402
0.1V
H-VCO, VIF-VCO & S-TRAP fo ADJUSTMENT
NO ADJUSTMENT POINT ADJUSTMENT CONDITION / PROCEDURE WAVEFORM OR OTHERS
1 H-VCO ADJ
(Manual Adj)
(I2C BUS CONTROL) (1) In No signal (RASTER) condition.
(AUTO & MANUAL ADJ) (2) Go to service mode, choose service data
V25
.
(3) Connect oscilloscope to
IC801 pin13 (H-OUT)
, adj
V25
until freq
become
15.735 ± 0.2KHz.
(Auto Adj)
(1) In No signal (RASTER) condition.
(2) Go to service mode.
(3) Choose service data
V25
, by pressing R/C
"AUTO H-VCO"
key, OSD will appear "OK"
at screen.
(4) If appear "NG" pls repeat step 3.
2 VIF-VCO ADJ
(Manual Adj)
*NOTE:
(I2C BUS CONTROL) (1) In No signal (RASTER) condition. This adjustment must be done after aging
(AUTO & MANUAL ADJ)
(2) Go to service mode, choose service data
V14
at least 3 minutes.
(3) Connect oscilloscope to
IC801 pin7 (AFT)
, adj
V14
until voltage become
2.5 ± 0.5 V DC
(Checking spec : 2.50 ± 1.5 V)
(Auto Adj)
(1) In No signal (RASTER) condition.
(2) Go to service mode, choose service data
V14.
(3) Press the R/C
"AUTO PIF-VCO"
key, OSD will appear "OK" at screen.
(4) If appear "NG" pls repeat step 3.
3 S-TRAP fo ADJ (
Manual ADJ
)
(I2C BUS CONTROL) (1) In No signal (RASTER) condition.
(AUTO & MANUAL ADJ) (2) Go to service mode, choose service data
V26.
(3) Connect oscilloscope to
TP 801 or IC801 pin 30
, adj
V26
until voltage become
Min
(below 5 V).
(
Auto Adj
)
(1) In No signal (RASTER) condition.
(2) Go to service mode, choose service data
V26.
(3) Press the R/C
"AUTO S-TRAP"
key, OSD will appear "OK" at screen.
(4) If appear "NG" pls repeat step 3.