Electrical Adjustment Instructions - Symphonic WFT20M4 Service Manual

ELECTRICAL ADJUSTMENT INSTRUCTIONS

General Note:
"CBA" is abbreviation for "Circuit Board Assem-
bly."
NOTE:
Electrical adjustments are required after replacing
circuit components and certain mechanical parts.
It is important to perform these adjustments only
after all repairs and replacements have been com-
pleted.
Also, do not attempt these adjustments unless the
proper equipment is available.
Test Equipment Required
1. NTSC Pattern Generator (Color Bar W/White
Window, Red Color, Dot Pattern, Gray Scale,
Monoscope, Multi-Burst)
2. DC Voltmeter
3. Oscilloscope: Dual-trace with 10:1 probe,
V-Range:0.001~50V/Div,
F-Range: DC~AC-60MHz
4. Plastic Tip Driver
5. Remote control unit: Part No. NE154UD, NE142UD,
N0132UD, N0108UD,
NE141UD, or NE122UD
6. DC power supply 13.2V/5A
How to make Service remote control unit:
1. Prepare normal remote control unit.
(Part No. NE154UD,
N0108UD, NE116UD, NE153UD, NE141UD, or
NE122UD)
Remove 3 Screws from the back lid. (Fig. 1-1)
2. Added J1 (Jumper Wire) to the remote control CBA.
(Fig. 1-2)
SCREWS
REMOTE CONTROL UNIT
REMOTE CONTROL CBA
NE116UD, NE153UD,
NE142UD, N0132UD,
Fig. 1-1
Fig. 1-2
5-1
How to set up the service mode:
Service mode:
1. Use the service remote control unit.
2. Turn the power on. (Use main power on the TV
unit.)
3. Press "SLEEP" button on the service remote con-
trol unit. Version of micro computer will display on
the CRT. (Ex: 058-0.06)
4. Check the display on the lower left is "2200" and if
it is not "2200," set it at "2200" according to "2. Ini-
tial Setting."
1. +B Adjustment
Purpose: To obtain correct operation.
Symptom of Misadjustment: The picture is dark and
the unit does not operate correctly.
Test Point Adj. Point
TP601(+B)
VR661
TP300(GND)
Tape M. EQ.
--- DC Voltmeter
Note: TP601, TP300(GND), VR661 --- Main CBA
1. Connect DC Volt Meter to TP601 and TP300(GND).
2. Adjust VR661 so that the voltage of TP601 becomes
+114±0.5V DC.
Mode Input
--- ---
Spec.
+114±0.5V DC.
L2403EA