Adjustment Procedures High Voltage Regulation; Main/Sub Y Level - Mitsubishi Electric VS-50111 Service Manual

MODELS: VS-50111 / VS-60111 / WS-48311 / WS-55311 / WS-55411 / WS-65311 / WS-65411 / WS-73411
[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
Video Input
Input Terminal
[Video Circuit]

2. Main/Sub Y Level

Measuring
Oscilloscope
Instrument
JA Connector pin 17
Test Point
JB Connector pin 1
------
Ext. Trigger
Measuring
------
Color Bars
Range
Input Signal
Video Input
Input Terminal
Purpose:
To set the CRT Anode voltage.
Symptom:
Dark Picture
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.
CONVERGENCE MODE
Activate ........MENU-2-2-5-9
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)
Purpose
To set picture luminance
Excess or insufficient brightness.
Symptom:
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 17 (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 17.
(If it cannot be adjusted within this range, set to the lower value)
7. Move the oscilloscope to connector JB pin 1 (Sub-Y).
8. Select Item "3 YDRS" in the Sub Matrix function.
9. Adjust the data to equal the MAIN-Y Gain (+0.0V -0.1V).
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CIRCUIT ADJUST MODE
Activate ........ MENU-2-2-5-7
Function .................AUDIO
Item No. .................VIDEO
Adjust Data ...........ADJUST
Save Data .... .........ENTER
Exit ..............MENU (twice)