Adjustment Procedures High Voltage Regulation; Main/Sub Y Level - Mitsubishi Electric WT-42313 Service Manual

[HV Circuit]
1. HV Regulation
Measuring
DC Voltmeter
Instrument
Test Point
DT connector pins 3 & 6
------
Ext. Trigger
Measuring
-------
Range
Video Signal
Input Signal
Monoscope
Input Terminal
Video Input
[Video Circuit]

2. Main/Sub Y Level

Measuring
Oscilloscope
Instrument
JA Connector pin 14
Test Point
JA Connector pin 4
------
Ext. Trigger
Measuring ------
Color Bars
Range
Input Signal
Input Terminal Video Input
MODEL: WT-42313 / WT-42413
To set the CRT Anode voltage.
Purpose:
Dark Picture
Symptom:
Note: This adjustment must be rechecked following Adjustment 9 CRT Cutoff.
1. Supply a video monoscope signal.
2. Set Contrast to maximum, and Brightness to mid position.
3. Connect a DC volt meter between pins 3 and 6 of the DT connector.
(Positive lead to pin 3)
4. Activate the Conv-Misc Mode.
5. Select Item "1 HVOL" (screen goes black).
6. Adjust Item "1 HVOL" for 15.4V ±0.05V on the meter.
7. Save data and exit the Conv-Misc mode.
8. Confirm that the voltage does not change more than 0.15V.
Note: This adjustment must be performed if E2RESET or Convergence E2RESET
are activated.
To set picture luminance
Purpose
Symptom:
Excess or insufficient brightness.
1. Supply a color bar signal to a Video Input (not an RF input).
2. Select the color bar signal for both the main and sub pictures.
3. Connect the oscilloscope to connector JA pin 14 (Main-Y).
4. Activate the Adjustment Mode
5. Select Item "3 YDRM" in the Main Matrix function.
6. Adjust the data so the Main-Y signal is between 0.71 Vp-p max. and 0.66 Vp-p
min. at JA pin 14.
(If it cannot be adjusted within this range, set to the lower value)
7. Move the oscilloscope to connector JA pin 4 (Sub-Y). Activate PIP if the
waveform is unstable.
8. Select Item "3 YDRS" in the Sub Matrix function.
9. Adjust the data to equal the MAIN-Y Gain (+0.0V -0.1V).
Page 25
CONVERGENCE MODE
Activate ........MENU-0-3-5-9
Misc. ........................."6"
Coarse........................"5"
Fine ..........................."4"
Color (R,G or B)......AUDIO
Item No..................VIDEO
Adjust/Move..........ADJUST
Cursor Toggle.........ENTER
Save & Exit.....MENU (twice)
CIRCUIT ADJUST MODE
Activate ........ MENU-0-3-5-7
Function .................AUDIO
Item No. .................VIDEO
Adjust Data ...........ADJUST
Save Data .... .........ENTER
Exit ..............MENU (twice)