Wednesday, July 13, 2016

RCA MR29TF18 – TCL29E20S6 – How to enter service mode – Adjustments - Schematic

Used ICs: TMPA8809 – 4052 – TDA8944 – MSP3425G – TDA8177 – TDA16846 – TC90A49P – BCK4901[LOT]
Enter Factory Mode
Simply press the “SERVICE” key on the factory remote handset.
Press 1 2 3 4 5 6 7 8 9 0 NOTEBOOK,CAPS, DISPLAY ,SLEEP, CALENDAR ,COLOR/INS,FAVORITE,RECALL” you can switch in the sub-menus of  FAC01~FAC18 in turns.
Press P+ P- to choose the items.
Press V+ V- to adjust the data.
Press  OK and P+ P- to switch in the sub-menus of FAC19~FAC23
Exit Factory Mode
Press the “SERVICE” key on the factory remote handset. All changes in factory data will be saved in EEPROM automatically.
Aging Mode - Be used for aging before adjustment in Factory Mode.
Vertical doesn’t Work - Be used for Screen & Focus voltage adjustment. In Factory Mode, press “ TV/AV” to enter and exit.
White balance adjustment Mode - Be used for White balance adjustment. In Factory Mode, press“ BUS OFF” to enter and exit.
Default Value OK mode - Be used for default value setting before TV leaves Factory. In Factory Mode, press “S. EFFECT” to enter default value. “Wait” will be displayed in screen, when it is finished, “OK” will be displayed. It will exit factory mode automatically.
Note: Now press “SERVICE” cannot enter factory mode, you have to take the following steps to enter:
1. Setting Volume to Zero.
2. Press “V-” in cabinet and Press “Display” in RC simultaneously.
Circuit Diagram and PWB
Adjustments
1. BAdjustment
Apply Philips Test pattern signal in normal status, adjusting VR821 to make B+=130V±0.5V.
2. RF AGC adjustment
Observe monitor the collector waveform of Q101 with the probe of Oscilloscope.
Select channel 2 (>70dB) from the antenna input. Enter D-mode, select menu6 to adjust RFAGC item until the monitor peak value to 0.8Vp-p.
3. Sound Amplifier Adjustment
1) Apply 45.75 IF signal which is >60dB from P1101
2) Adjusting T1101 to make the voltage of Pin 15 in IC1101 is 2.5+0.05V.
4. Screen & Focus voltage adjustment
1) Apply pattern signal in normal status, enter D-mode, press “TV/AV” button to turn off the vertical output. (Note: The default value of RC/GC/BC is 80, and GD/BD is 40)
2) Adjust the SCRREEN switch on the flyback transformer to make a horizontal shining line just visible on the screen.
3) Turn on the vertical output; adjust the “FOCUS” on the flyback transformer to obtain the optimum focus.
5. White balance adjustment (NORMAL)
1) Apply Black and White Signal in normal status, enter into Factory Mode and select Menu 1.
2) Using analyzer to test the black signal part, adjust RCUT, GCUT, BCUT to make X=284, Y=299.
3) Using analyzer to test the white signal part, adjust BDRV, GDRV to make X=284, Y=299.
4) Adjusting Brightness and Contrast from Min to Max, repeat step 2)~3) to make X=284, Y=299.
Note: M134 chassis can adjust white balance automatically. In factory mode, press “I2C BUS” to enter in.  The white balance in the other two colors temperature is Warm (296, 296), Cool (279, 265).
6. Adjustment of Sub-brightness
1) Apply the Grey-scale/Color bar (NTSC signal) to the AV input, in normal status.
2) Enter into Factory Mode and select Menu 5, select BRTC to adjust the sub-brightness, until that the 2nd dark bar of 8 level Grey scale just can be seen.
7. Picture geometric adjustment
1) Apply the Philips standard testing pattern in normal status, then enter menu 3, adjusting the following data to get the min-distortion.
HPOS5/6 Horizontal Center PARA5/6 Level TRAP5/6
 Trapezia HSIZE5/6 Horizontal Size CNRT5/6  Top CNRB5/6  Bottom
2) Apply the Philips standard testing pattern in normal status, then enter menu 3, adjusting the following data to get the min-distortion.
HIGH5/6 (Height) VP50/60 Vertical Center

VLIN5/6 Linearity  VSC5/6 Vertical-S Correction
8. BTSC/SAP Function checking
It needn’t to adjust the BTSC/SAP, but you have to check where it does work.