. Various china ch m28 with tmpa880scsn tda9874 - adj 152 free download

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TCL OVERSEAS HOLDINGS LIMITED Service Manual39 PART V. Adjusting Description Flowchart chart of alignment procedure for M28 chassis: B+ NICAM Electrical properties RF AGC adjustment Adjustment checking for chassis adjustment Sub-brightnes White balance Adjustment of screen Sub-color & Sub-tint s Adjustment Adjustment Aging voltage and focus adjustment Pincushion and screen Screen center & size Screen center & size QC width adjustment adjustment (PAL) adjustment (NTSC) Checking ALIGNMENT PROCEDURE FOR M28 CHASSIS: I) Adjustment of +B Voltage 1. Apply 110-240VAC( 5V) to mains power input, and Philips standard testing pattern to RF input. 2. Adjust VR830 in STANDARD mode until voltage at (B+) is 112V 0.25V. II) NICAM Adjustment (for NICAM model only) 1. Apply a 38.9MHz color bar with NICAM signal to the IF input. 2. Monitor the DC voltage at pin 15 of IC1101. 3. Adjust T1101 until the voltage at pin 15 of IC1101 becomes 2.5 +/- 0.1V. 4. Then check the waveform at pin 4 and 6 of P1103 and it must show correct audio signal. III) The alignment of RFAGC (choose A or B) A) 1. Connect the detector shown below to collector of Q101. 2. Receive a grey scale signal with 70dB V amplitude. 3. Adjust RFAGC item until the output of the detector becomes 0.8Vpp B) 1. Receive a grey scale signal with 60dB V amplitude. 2. Adjust RFAGC data until the noise of the picture just disappear. IV) Adjustment of Sub-contrast, Sub-tint and Sub-colour for NSTC and PAL signal. 1. Enter D-mode, and connect the probe of Oscilloscope to the conjunction between R201 and P201 (B-out). 40 Service Manual TCL OVERSEAS HOLDINGS LIMITED 2. Apply the Grey-scale/Colour-bar (NTSC signal) to the AV input, in STANDARD status. 3. Select CNTC to adjust the sub-contrast, until that the amplitude "A" is 2.2VP-P as shown below. 4. Select COLC to adjust the sub-colour by tuning the amplitude of "a" and "d" to the same. 5. Select TNTC to adjust the sub-tint by tuning the amplitude of "b" and "c" to the same. 6. Apply the Grey-scale/Colour-bar (PAL signal) to the AV input, in STANDARD status. 7. Select COLP to adjust the sub-colour by tuning the amplitude of "a", "b", "c" and "d" to the same. V) Adjustment of Focus, Screen Voltage and Sub-brightness 1. Receive a crosshatch pattern. 2. Adjust the "FOCUS" VR on the flyback to make the picture clear. 3. Enter D-mode and press "MUTE" key and the screen will become a horizontal line. Then adjust the "SCREEN" VR on the flyback transformer to set the intensity of the line to a minimum visible level (the line can just be seen). 4. Press "MUTE" key again and the TV will become full raster. 5. Selec