Service Manuals, User Guides, Schematic Diagrams or docs for : . Various CHINA TV TV Div Service Mode`s chinese TV`s china_ctv37v10_ch_3401_3y01__ctv55v10_ch_4401_4y01___with_la8633xx_la7681__-_adj_937

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CHASSIS ALIGNMENT
1.   PIF Adjustment




     1-1 Tuner AGC connects to GND. Pattern Generator outputs 38.9MHz R.F. signal and connects to tuner
         IF output terminal or pin 5 of saw filter.
     1-2 Connect Digital voltmeter across C227. DC Regulated power supply positive terminal output +20V
         to pin 1 of IC302 and negative terminal of D608. DC Regulated power supply negative terminal
         connects to pin 2 of IC302.
     1-3 Adjust L203 coil to obtain 3.6V Digital voltage meter reading.

2.   System NTSC Adjust(L108)
     2-1 Tuner AGC connects to GND. Connect Sweep Signal Generator to tuner IF output terminal. Sweep
          oscilloscope V-IN terminal connects to C109. And connect Q102 'b' pole to the power terminal of
          R104. (shown in FIG.2)

 Sweep Signal           Sweep        DC Regulated
  Generator           Osciloscope    Power Supply
     2-2 Apply +20V DC across IC302 as shown in FIG.2.
     2-3 Adjust L108 to obtain waveform as following. There will be no alignment to it without NTSC
         system.




3.   B+ adjustment
     3-1 Disconnect horizontal load. Connect a light bulb (100 W) AC 250V across C321.
     3-2 Connect 220V AC 50 Hz to CN601 and switch on power switch.
     3-3 Test the voltage with digital voltage meter between C321 two terminals.
     3-4 Adjust VR601 to obtain +110V +/- 0.5V.

4.   AGC alignment
     4-1 Receive 60dB +/- 2dB RF signal. Connect Digital voltmeter positive terminal to AGC terminal of
          TUNER and negative terminal to GND.
     4-2 Press "MENU" key twin, till the PICTURE MENU appears, then press "Q.VIEW" key, "MUTE" key to
          turn on CPU. TV SET will go to factory mode. Press "TIMER" key to go to the next factory menu. Go
          to "MENU 3" status by this means.
     4-3 Select RF.AGC by pressing "CH+" or "PROG+" and "CH." or "PROG-" keys. Adjust "VOL+" and
          "VOL-" keys to obtain 4V Digital voltage meter reading.
     4-4 Press "MENU" key to exit factory mode.
COMPLETE MACHINE GENERAL ADJUSTMENT
1.   Go to factory mode according to 4-4-2 before warm up line,

2.   Focus Adjustment.
     2-1 Receive monoscope pattern.
     2-2 Set TV to work in dynamic status.
     2-3 Adjust the focus knob of FBT to get the clearest picture.

3.   Screen Voltage Adjustment.
     3-1 Go to factory mode "MENU 2" status according to 4-4-2.
     3-2 Select "V-KILL" by pressing "CH+" or "PROG+" and "CH-" or "PROG-" keys..
     3-3 Press "VOL+" key all the time, Adjust the screen knob of FBT to get a horizontal faintness beam
          line. Then loose "VOL+" key.

4.   White Balance Adjustment (Applied In factory only)
     4-1 Set the TV set to AV mode. Receive black white pattern (Color Temperature test pattern). 4-2
          Insert 6 Pin Service flat cable into CN002. Press adjustment keys, and then go to automatic white
          balance adjustment.
     4-2 After adjusting well, remove the 6 Pin Service flat cable.

4.   (1) White Balance adjustment (Applied when servicing)
     4-1 (1) Set the TV set to AV mode. Receive black white pattern (Color Temperature test pattern),
     4-2 (1) Put the test probe 1 of CRT color analyzer (CA-100) on the Low Bright area and the test probe
          2 on the High Bright area. Adjust bright and contrast to get 5nit of low bright area and 80 nit of
          high bright area.
     4-3 (1) Go to factory mode "MENU2" according to 4-4-2. Obtain Low Bright area to x=281and y=311
          by adjusting R.bias and B.bias. Obtain High Bright area to x=281and y=311 by adjusting R.drive
          and B.drive. Obtain both area to x=281 and y=311 by adjusting the two status repeatedly.

5.   Sub-bright adjustment
     5-1 Receive GREY SCALE signal.
     5-2 Set TV at normal mode.
     5-3 Get into factory mode, adjust sub-bright option to make the picture same as below.




     The first bar is totally dark. Brightness will begin to appear from the second bar.

6.   Vertical Size and PinCushion Adjustment
     6-1 Receive monoscope pattern. Set TV standard status. Adjust V.size to obtain picture's vertical
           redisplay ratio more than 90% in factory mode "MENU1".
     6-2 Receive cross hatch pattern. Set TV standard status. Adjust V.LINE and V.SC to obtain picture's
           vertical pin cushion a good status in factory mode "MENU1".
     6-3 Receive cross hatch pattern. Set TV standard status. In factory mode "MENU1" adjust V.POSITION
           to obtain picture's vertical center at the center of CRT screen.

7.   Horizontal Center Adjustment
     Receive PHILIPS PATTERN. Set TV standard status. Adjust H.PHASE to obtain horizontal center at the
     center of CRT screen.

8.   Secam color decoder alignment.
     Receive the GREY SCALE /COLOR BAR signals. Enter into the factory mode. Adjust the values of Secam
     R-Y DC and Secam B-Y DC to make the gray scale to the normal color.

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