Sharp 21FL91, Service Manual

Page: 18 / 46

18
18-1
18-2
21FL91
ADJUSTMENT ITEM ADJUSTMENT POSITION CONTROL PRE-ADJUST REQUIREMENT CONTENT INPUT CONDITION OUTPUT ADJUSTMENT PROCEDURE
RF-A
GC
V08
STEP RANGE
0-127
I 2
C CONTROL
OPTION SET
UP
, BUS SET
UP
US10CH HALF COLOR BAR RF INPUT FIELD STRENGTH
53dB
µ
V
(FIX)
TUNER
AGC
TERMINAL
(TP
201) OR CR
T
DISPLA
Y
CONFIRMA
TION
(A
T SELF ADJUSTMENT MODE)
1.
GO
T
O
SER
VICE MODE
2.
GO
T
O
SER
VICE DA
T
A
V08
, PRESS R/C
T
O
OPEARA
TE
AUT
O-AGC
KEY
AND
CONFIRM
THE
OK
DISPLA
Y
ON
THE SCREEN.
3.
IF
APPEAR NG PLS REPEA
T
STEP
2
AGAIN.
(A
T MANU
AL ADJUSTMENT MODE)
1
.
ADJUST
THE V08 BUS DA
T
A
UNTIL
AGC TERMINAL
VOL
T
AGE BE-
COME MAXIMUM,
THEN DROP
0.1V BELOW MAXIMUM VOL
T
AGE.
2.
CHANGE
THE
ANTENNA
INPUT
SIGNAL
T
O
63-67 dB
µ
V
, AND
MAKE
SURE
THERE IS NO NOISE
3
.
CHANGE
THE
ANTENNA
INPUT
SIGNAL
T
O
90-95 dB
µ
V
T
O
BE SURE
THA
T
THERE IS NO CROSS MODULA
TION BEA
T
.
[CHECKING SPEC] MAX - 0.1V dc
ADJUSTMENT ITEM ADJUSTMENT POSITION CONTROL PRE-ADJUST REQUIREMENT CONTENT INPUT CONDITION OUTPUT ADJUSTMENT PROCEDURE
1)
IN SER
VICE MODE, SET
V04&V11&V12&V13
T
O
127;
V14&V15
TO
64, GET
IN
Y
-MUTE BY
R/C
AND SET
V19
T
O
“1”, PICTURE
APPEAR
IN CUT
-OFF CONDITION
2
)
ADJUST
THE SCREEN SO
THA
T
CUT
-OFF LINE
APPEAR IN LOW
BRIGHT
,
THEN JUDGE
THA
T
WHETHER
THE CUT
-OFF LINE
APPEAR
IN RED OR GREEN OR BLUE COLOR, IN
THIS CONDITION V1
1=R-
CUT
OFF
, V12=G-CUT
OFF
, V13=B-CUT
OFF
, FIX
THE DA
T
A
OF
THE
COLOR
APPEAR IN CUT
OFF LINE
AND USE R/C
T
O
ADJUST
THE
OTHER
TWO CUT
-OFF DA
T
A
SO
THA
T
CUT
-OFF LINE COLOR BE-
COME WHITE.
3)
TURN
THE SCREEN VR OF FBT
SO
THA
T
CUT
-OFF LINE JUST
DIS-
APPEAR
AND USE R/C
T
O
SET
V19
T
O
“0”, NEXT
DISABLE
THE
Y
-
MUTE SO
THA
T
PICTURE
APPEAR IN NORMAL
MODE.
SCREEN
V11,V12,V13
STEP RANGE
0-255
I
2
C CONTROL
OPTION SET
UP
, BUS SET
UP
WINDOW P
A
TTERN OR US4CH LION HEAD
220V
CONFIRMA
TION ON CR
T
DISPLA
Y
[V
OL
T
A
GE CONFIRMA
TION]