Adjustment - Sharp 21V-FS700S Service Manual

21V-FS700S

[2] ADJUSTMENT

ADJUSTMENT PRECAUTION: Makesure TV Set is in "Normal Condition" before switch to Service Mode for Adjustment.
1. PIF ADJUSTMENT CHECKING
NO ADJUSTMENT POINT
RF-AGC TAKE OVER
1
POINT ADJUSTMENT
(I2C BUS CONTROL)
(AUTO & MANUAL ADJ)
2. FOCUS ADJUSTMENT
NO ADJUSTMENT POINT
1 FOCUS
ADJUSTMENT CONDITION / PROCEDURE
(1) Receive "PAL COLOR BAR" signal.
Signal Strength: 53 ± 1dBµV (75 ohm open)
(2) Connect the oscilloscope to JA402 (Tuner's
AGC Terminal) as shown in figure 3-1.
OSCILLOSCOPE
+
0.1V
1.0V -
+
-
BIAS BOX
(3) Call "01 RF-AGC" mode in service mode.
Adjust the "01RF AGC" bus data to obtain
the Tuner output pin drop 0.1~1.0V 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.
ADJUSTMENT CONDITION / PROCEDURE
(1) Receive the "Monoscope Pattern" signal.
(2) Press R/C to set Picture NORMAL condition.
(3) Adjust the focus control to get the best
focusing.
3 – 13
WAVEFORM OR OTHERS
* for Auto ADJ
(1) Receive "PAL COLOR BAR"
signal
signal strength :
53 ± 1 dBµV (75 ohm open).
(2) Go to service mode.
(3) Go to service data 01 RF-AGC,
TV SET
press R/C to operate auto key
TP201
(Hex C1). Blue display with OK
sign indicates the adjustment is
working properly
(4) If appear red display with NG
sign, increase data some step
and please repeat step 2.
(5) Proceed step 3 & 4 in manual
mode.
WAVEFORM OR OTHERS
Focusing
Point
(middle of
center and
edge of
monoscope
pattern)