Electrical Adjustments - Memorex MT1136A Service Manual

1. BEFORE MAKING ELECTRICAL
ADJUSTMENTS
Read and perform these adjustments when repairing the
circuits or replacing electrical parts or PCB assemblies.
CAUTION
Use an isolation transformer when performing any
*
service on this chassis.
Before removing the anode cap, discharge electricity
*
because it contains high voltage.
When removing a PCB or related component, after
*
unfastening or changing a wire, be sure to put the wire
back in its original position.
Inferior silicon grease can damage IC's and transistors.
When replacing IC's and transistors, use only specified
*
silicon grease (YG6260M).
Remove all old silicon before applying new silicon.
1-1:Prepare the following measurement tools for

electrical adjustments.

1. Synchro Scope
2. Digital Voltmeter
2. BASIC ADJUSTMENTS
On-Screen Display Adjustment
In the condition of NO indication on the screen.
Press both VOL. DOWN button on the set and the channel
button (9) on the remote control more than 2 seconds
to appear the adjustment mode on the screen as shown
in Fig. 2-1.
NOTE
Use the channel buttons (1-8) on the remote control to
select the options shown in Fig. 2-1.
Press the channel button (0) on the remote control to
end the adjustments.
1. H/V
2. AKB
3. COLOR TEMP
4. PICTURE
5. OTHERS
6. TEST PATTERN
7.
8. (VOL TEST)
2-1: RF AGC DELAY
1. Receive an 80dB monoscope pattern.
2. Connect the digital voltmeter between the pin 2 of
CP101 and the pin 6 (GND) of CP101.
3. Activate the adjustment mode display of Fig. 2-1 and
press the channel button (5) on the remote control.
The Fig. 2-2 appears on the display.
4. Press the channel button (1) on the remote control.
5. Press the VOL. UP/DOWN button on the remote control
until the digital voltmeter is 2.0 ± 0.05V.
ELECTRICAL ADJUSTMENTS
0. END
Fig. 2-1
1. RF AGC DELAY
2. VIDEO LEVEL
3. FM LEVEL
4. OSD H
5. CUT OFF
6. X-RAY
7.
8.
2-2: CUT OFF
1. Using the remote control, set the brightness and
contrast to normal position.
2. Activate the adjustment mode display of Fig. 2-1 and
press the channel button (5) on the remote control.
The Fig. 2-2 appears on the display.
3. Press the channel button (5) on the remote control.
4. Adjust the Screen Volume until a dim raster is obtained.
2-3: WHITE BALANCE
NOTE:
Adjust after performing adjustments in section 2-2.
1. Receive the color bar pattern.
2. Activate the adjustment mode display of Fig. 2-1 and
press the channel button (2) on the remote control.
The Fig. 2-3 appears on the display.
3. Adjust the adjustment mode display of Fig. 2-3 until
the white color is looked like a white.
1. AKB AUTO
2. R. BIAS
3. G. BIAS
4. B. BIAS
5. R. DRIVE
6. G. DRIVE
7. B. DRIVE
8. AGC AUTO
2-4: SUB BRIGHTNESS
1. Receive the monoscope pattern.
2. Using the remote control, set the brightness and
contrast to normal position.
3. Activate the adjustment mode display of Fig. 2-1 and
press the channel button (4) on the remote control.
The Fig. 2-4 appears on the display.
4. Press the channel button (1) on the remote control.
5. Press the VOL. UP/DOWN button on the remote control
until the white 10% is starting to be visible.
1. BRIGHT
2. CONTRAST
3. COLOR
4. TINT
5. SHARPNESS
6. OSD CONT
7.
8.
D1-1
0. RETURN
Fig. 2-2
0. RETURN
Fig. 2-3
0. RETURN
Fig. 2-4