Mitsubishi Electronics VS-60609 CRT Circuit Purpose, CRT Cutoff Symptom, Abbr Data Service Mode

MODELS: VS-45609 / VS-50609 / VS-55609 / VS-60609 / VS-60719 / VS-70709

[CRT Circuit]		Purpose:	To set the cutoff point for all three CRTs.
7. CRT Cutoff		Symptom:	Monchrome has a color tint, or incorrect brightness.
Measuring	Oscilloscope	1. Select an External Input with no signal.
Instrument
Test Point	TP6R, TP6G, TP6B	2. Enter the Service Mode, VCJ Function.
		3. Set the data to the values given for the Items listed in the Table.
Ext. Trigger	------	4. Connect the oscilloscope to TP6R.
Measuring	50V per division/ 2 msec	5. Adjust the Red SCREEN VR so the black level is 200V, as shown below, or to
		206 ±1VDC using a DC Voltmeter.
Range		6. Repeat Steps 4 and 5 to set the Blue and Green SCREEN VRs, using TP6G
Input Signal	None
		and TP6B.
Input Terminal	Video Input	Note: The White Balance Adjustment must be performed after Cutoff Adjustment.
			VCJ Function
			ITEM	ABBR.	DATA
SERVICE MODE			7	BRTH	31
			8	CTRH	7
Activate …….. MENU-0-1-5-7
			9	CTGH	10
Function …...………..AUDIO
			10	CTBH	7
Item No. ……….…….VIDEO
Adjust Data ….…….ADJUST
Save Data …. ………ENTER
Exit …………..MENU (twice)

[CRT Circuit]			Purpose:	To set the CRTs white level
8. White Balance			Symptom:	Monchrome has a color tint.
	(High Color Temperature)
Measuring		DC Meter	Note: This adjustment must be performed after the CRT Cutoff and Focus
Instrument
Test Point		R6G30, R6B30	Adjustments.
			High Color Temperature White Balance
Ext. Trigger		------
			1. Supply a Full White Raster signal to the Video Input.
Measuring		-------
			2. Enter the Service Mode, VCJ Function.
Range
			3. Adjust Items “11 RDRH” and “13 BDRH” for optimum white at the center of the
Input Signal		Full White Raster
			screen.
Input Terminal		Video Input	Note: If the Cutoff level changes during the adjustment, use Items “8 CTRH”
			and “10 CTBH” to touch up the Cutoff level. Then readjust “RDRH” and
			“BDRH”.
	SERVICE MODE
			4. Save data and exit the Service Mode.
	Activate …….. MENU-0-1-5-7
			5. Use a DC Current Meter to measure each CRT’s current.
	Function …...………..AUDIO
			• The meters internal resistance must be less than 30 Ohms.
	Item No. ……….…….VIDEO
			• Lead length must be less than 30 CM.
	Adjust Data ….…….ADJUST		6. Connect the meter, in sequence, across each of the following resistors to read
	Save Data …. ………ENTER		the current for that respective CRT.
	Exit …………..MENU (twice)		• Green CRT ... across R6G30

•Blue CRT ...... across R6B30

7. The Green and Blue CRT current must not exceed the values given in Table 1.

Maximun CRT Current

CRT		CURRENT
Green		580 ua
Blue		530 ua
	Table 1

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