Sharp 21FL91, Service Manual

Page: 23 / 46

23
21FL91
23-1
23-2
ADJUSTMENT ITEM ADJUSTMENT POSITION CONTROL PRE-ADJUST REQUIREMENT CONTENT INPUT CONDITION OUTPUT ADJUSTMENT PROCEDURE
1)
CONNECT
100
µ
F ELECTROLL
YTIC CAP
ACIT
OR BETWEEN C3005
(-ve)-GND
2)
ADJUST
THE BUS DA
T
A
M02
UNTIL
THE OUTPUT
FREQUENCY
OF
39 PIN BECOME
AS SPECIFIED BELOW
.
NOTE:
T
O
MINIMIZE
THE PR
ODUCTION
TIME,
ITEM 1) CAN IGNORE.
IF ITEM 2) CAN'T BE ADJUST
, THEN ITEM 1) IS REQ
UIRE.
MTS+VCO ADJUSTMENT
M02
STEP RANGE
0~63
I 2
C BUS CONTROL
OPTION SET
UP
, BUS SET
UP
, VCO
ADJ, RF-AGC
SIGNAL
WITHOUT
NOISE (SIGNAL
WITHOUT
SOUND MODULA
TION)
AC 200V IC 3001 39 PIN
[CHECKING SPEC] 62.94
±
0.75kHz (CHECKING SPEC : 62.94
±
1.20kHz)
ADJUSTMENT ITEM ADJUSTMENT POSITION CONTROL PRE-ADJUST REQUIREMENT CONTENT INPUT CONDITION OUTPUT ADJUSTMENT PROCEDURE
1)
ADJUST
M03
DA
T
A
UNITILL
OK
DISPLA
Y
ON SCREEN
ADJUST
THE
BUS DA
T
A
IN CENTRE OF
THE RANGE.
FIL
TER ADJUSTMENT
M03
STEP RANGE
0~63
I 2
C BUS CONTROL
OPTION SET
UP
, BUS SET
UP
, VCO
ADJ, RF-AGC, MS-LEVEL, MTS-VCO
SINE W
A
VE (9.4kHz, 600mV
rms)
PIN 14 (FROM C3005 -
TERMINAL)
CONFIRM BY
CR
T
SCREEN
[CHECKING SPEC] REFER
T
O
ABOVE (CHECKING SPEC :
±
2 STEP
T
O
CENTRE)