Mitsubishi Electronics mitsubishi specifications Video Circuit Purpose

MODEL: WD-52327 / WD-62327

[Video Circuit]		Purpose:		To set picture luminance
1. Main/Sub Y Level		Symptom:		Excess or insufficient brightness.
Measuring	Oscilloscope	1.	Supply a color bar signal to a Video Input (not an RF input).
Instrument
Test Point	JA-22 & JB-3	2.	Select the color bar signal for both the main and sub pictures.
		3.	Connect the oscilloscope to connector JA pin 22. (Main-Y)
Ext. Trigger	------	4.	Activate the Adjustment Mode (MENU-5-7-5-7)
Measuring	------	5.	Select the “MAIN MTRX” function. (AUDIO button)
		6.	Select adjustment Item “39 SCNT”. (VIDEO button)
Range		7.	Adjust the data for 0.71 ~ 0.76 Vp-p at JA pin 22.
Input Signal	Color Bars
			(If it cannot be adjusted within this range, set to the lower value)
Input Terminal	Video Input	8.	Move the oscilloscope to connector JB pin 3. (Sub-y)
		9.	Select the “SUB MTRX” function. (AUDIO button)
		10.	Select adjustment Item “39 SCNT”. (VIDEO button)
CIRCUIT ADJUST MODE		11.	Adjust the data to equal the MAIN-Y Gain (+0.0V -0.05V).
Activate …….. MENU-5-7-5-7		12.	Press “ENTER” to save data changes.
Function …...………..AUDIO
Item No. ……….…….VIDEO
Adjust Data ….…….ADJUST
Save Data …. ………ENTER
Exit …………..MENU (twice)

[Video Circuit]					Purpose:		To set the sub picture color level.
2. Main/Sub Color Level					Symptom:		Main and sub pictures color levels differs.
Measuring		Oscilloscope		1.		Supply a color bar signal to a Video Input.
Instrument
Test Point			JA-20 & JB-5	2.		Select the color bar signal as the source for both the main and sub picture.
				3.		Connect an oscilloscope to connector JA pin 20 (main Cr).
Ext. Trigger	------			3.		Activate the Adjustment mode (MENU-5-7-5-7)
				4.		Select the “MAIN MTRX” function (AUDIO button).
Measuring		200mV/div
				5.		Select adjustment item “41 SCLR” (VIDEO button)
Range		20usec/div		6.		Adjust the data for 0.81 ~ 0.86 Vp-p min. at JA pin 20.
Input Signal
		Color Bars				(If it cannot be adjusted within this range, set to the lower value).
Input Terminal		Video Input		7.		Move the oscilloscope to connector JB pin 5 (sub Cr).
				8.		Select the “SUB MTRX” function (AUDIO button).
				9.		Select adjustment item “41 SCLR” (VIDEO button).
				10.		Adjust data so the Sub Cr amplitude equals that of the Main Cr.
				11.		Press “ENTER to save data changes.

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