Rf Agc Alignment; Screen And Focus Adjustment - Qls 21F1 Service Manual

TCL-THOMSON Electronics R&D Center (Shen'Zhen Lab)

3.2 RF AGC alignment

3.2.1 Method 1
A. Connect the detector as shown below (Picture 3.2) to collector of Q101.
B. Receive a grey scale signal with 70dB V amplitude.
C. Enter P-Mode, press "6" key on RC to select "AGCT".
D. Adjust AGCT item until the output of the detector becomes 0.8Vpp
3.2.2 Method 2
A. Receive a grey scale signal with 60dB V amplitude.
B. Enter P-Mode, press "6" key on RC to select "AGCT".
C. Adjust the "AGCT" value until the hint display "AGC" just change between "0" and "1".
3.3 Screen & Focus adjustment
*Notes: Alignment below should be done after 15 minutes warm up of TV.
1. Input cross hatch pattern signal to RF input.
2. Enter P-Mode.
3. Press "0" key on the RC and the screen will become a horizontal line.
4. Adjust the "SCREEN" VR of the FBT until the horizontal line can just be seen barely
(minimum visible intensity).
Adjust the "SCREEN" VR
5. Press "0" key again on the RC to exit the screen voltage adjustment mode.
5. Adjust the "FCOUS" VR of the FBT until the vertical line and horizontal line becomes
clear, like picture 3.3.
Chassis Name NX56-LA
Issued on 2008-05-19
Updated on 2010-01-27
Collector
of Q101
Picture 3.2
Serial No.
Page
Version
To CRO
Page 7 of 15
2.2