Main / Sub Y Level & Hv Regulation - Mitsubishi WS-55517 Service Manual

MODELS: WS-55517 / WS-65517 / WS-73517
[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
Instrument
Oscilloscope
Test Point
JA connector pins 26 &35
Ext. Trigger
------
Measuring
------
Range
Input Signal
Color Bars
Input Terminal
Video Input
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. Sent 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 ±0.2V 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.
Purpose
To set picture luminance
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 25.
4. Activate the Adjustment Mode
5. Select Item "15 YDMR" in the MAIN MTRX function.
6. Adjust the data for 0.66 Vp-p min.- 0.71 Vp-p max. at JA pin 25.
(If it cannot be adjusted within this range, set to the lower value)
7. Move the oscilloscope to JA pin 40.
8. Select Item "15 YDRS" in the SUB MTRX function.
9. Adjust the data to equal the MAIN-Y Gain (+0.0V -0.05V).
CIRCUIT ADJUST MODE
Activate ........ MEN U-2-4-5-7
Function ... ......... .....AUD IO
Item No. ...... ...........VIDEO
Adjus t Data ...........AD JU ST
Save Data .... ......... ENTER
Exit ......... .....MEN U (twice)
Page 27
CONVERGENCE MODE
Activate ... .....MEN U-2-4-5-9
Mis c. ......... ......... .... ..."6"
C oars e... ......... ............"5"
Fine ......... ............ ......"4"
C olor (R ,G or B)...... AUD IO
Item No...... ............VIDEO
Adjus t/Move...... ....ADJUST
C urs or Toggle.........EN TER
Save & Exit.....MEN U (tw ice)