Electrical Adjustment Instructions - Sylvania SRT2227S 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. N0127UD or N0132UD
or N0105UD or N0108UD
6. DC power supply 13.2V/5A
How to make Service remote control unit:
1. Prepare normal remote control unit. (Part No.
N0127UD or N0132UD or N0105UD or N0108UD)
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
1. DC 120V Adjustment
Purpose: To obtain correct operation.
Symptom of Misadjustment: The picture is dark and
the unit does not operate correctly.
Test Point
TP601(+120)
TP300(GND)
Tape
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
+120±0.5V DC.
2. Black Strech Control Adjustment
Purpose: To show the fine black color.
Symptom of Misadjustment: Black color will not
appear correctly.
Note: Use Service remote control unit.
1. Enter the Service mode. (See page 5-1)
2. Press " 6 " button on the Service remote control
unit. " B-S " is indicated.
3. Press " CH o / p " buttons on the Service remote
control unit so that display will change " OFF ", " 0
", " 1 ", " 2 " and " 3 ". Then choose " B-S OFF ".
4. Press " 6 " button on the Service remote control
unit. " B-S*2 " is indicated.
5. Press " CH o / p " buttons on the Service remote
control unit so that display will change " 0", " 1 ". "
2 " and " 3 ". Then choose " B-S*2 0".
6. Turn the power off and on again. (Main power but-
ton on the TV unit.)
Fig. 1-1
Fig. 1-2
5-1
Adj. Point
VR661
M. EQ.
--- DC Voltmeter
Mode Input
--- ---
Spec.
+120±0.5V DC.
L6200EA