Electrical Adjustment Instructions; Test Equipment Required; How To Enter The Service Mode; Dc 105V (+B) Adjustment - Magnavox CMWC13D6 Service Manual

ELECTRICAL ADJUSTMENT INSTRUCTIONS

General Note:
"CBA" is abbreviation for "Circuit Board
Assembly."
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 Win-
dow, Red Color, Dot Pattern, Gray Scale, Mono-
scope, Multi-Burst)
2. AC Milli Voltmeter (RMS)
3. DC Voltmeter
4. Oscilloscope: Dual-trace with 10:1 probe,
V-Range: 0.001~50V/Div,
F-Range: DC~AC-60MHz
5. Frequency Counter
6. Plastic Tip Driver
7. Color Analyzer
How to make service remote control
unit:
1. Prepare remote control unit (Part No. NE241UD).
Remove 4 screws from the back lid. (Fig. 1)
SCREW
Remote control unit (Bottom)
2. Cut off pin 10 of the remote control microprocessor
and short circuit pins 10 and 17 of the microproces-
sor with a jumper wire.

How to enter the Service mode:

Service mode:
1. Use the service remote control unit.
2. Turn the power on.
3. Press "DISC MENU" button on the service remote
control unit.
- "**h" ("**" differs depending on the models) is
indicated on the lower right of the screen.

1. DC 105V (+B) Adjustment

Purpose: To obtain correct operation.
Symptom of Misadjustment: The picture is dark and
unit does not operate correctly.
Test point
J1124(+B)
GND
Tape
---
Note:
J1124 (+B), VR1601 --- Main CBA
1. Connect the unit to AC Power Outlet.
2. Connect DC Volt Meter to J1124 (+B) and GND.
3. Adjust VR1601 so that the voltage of J1124 (+B)
becomes +105±0.5V DC.
Fig. 1
1-6-1
Adj. Point Mode
VR1601 ---
M. EQ. Spec.
DC Voltmeter
+105±0.5V DC
Plastic Tip Driver
Input
-----
T8200EA