Monday, December 05, 2022

LG 21FU1RLX -CRT TV – Service adjustments and schematic diagram

 

General Specification

Adjustments

(1) Because this is not a hot chassis, it is not necessary to use an isolation transformer. However, the use of isolation transformer will help protect test instrument.
(2) Adjustment must be done in the correct order.But the adjustment can be changed by consideration of mass production.
(3) The adjustment must be performed in the circumstance of 25±5°C of temperature and 65±10% of relative humidity if there is no specific designation.
(4) The input AC voltage of the receiver must keep rating voltage in adjusting.
(5) The receiver must be operated for about 20 minutes prior to the adjustment.
(6) Signal: Received, the standard colour signal.(65dB±1dB uV) LG standard signal means the digital pattern (PAL_EU 05CH,NTSC_US 13CH).

Focus adjustment

(1) Receive the Cross-Hatch Pattern.
(2) Set the picture condition on “DYNAMIC(CLEAR)” mode.
(3) Adjust the Focus volume of FBT, made the focus of the ¼ part vertical line is best.

Purity & Convergence adjustment
Adjustment should be operated when using the CPT (without ITC from CPT manufacturing place)
This adjustment must be done in the order of the following flowchart.

Colour purity adjustment
(1) It makes CPT or CABINET enough to demagnetization.
(2) Receive the signal of red raster.
(3) Unfasten DY and push DY to FUNNEL direction.
(4) Make R-L and be cantered as cross Purity Magnet. That time, 4 & 6 pole magnet should keep free gauss status.
(5) Make uniform RED Raster as moving DY, Check there is purity problem or not on R/G/B, white Raster. Then fix screw of DY.  (At this time, be careful about inclination and DY should be fixed keeping horizontality.)
(6) Check the TV set in direction of EAST, WEST, SOUTH, and NORTH. Adjust with supporting MAGNET when adjustment is not operated.
Convergence adjustment. 
These adjustments should be operated at the best condition of focus after finished purity adjustment.
(1) Receive the signal of cross hatch that BACK RASTER is black.
(2) Adjust brightness so that there are 9 ~12 dots.

(3) Widen two tabs of 4pole Magnet with equal angles and accord red, blue vertical lines at the center of screen.
(4) With keeping angle of "c.clause", rotate tab and accord red/blue, green vertical lines at the center of screen.
(5) Widen two tabs of 6pole Magnet with equal angles and accord red, blue vertical lines at the center of screen.
(6) With keeping angle of "e.clause", repeat the adjustment from c to e keeping in mind the movement of red, blue, green when the horizontal lines are twisted.
(7) Move the DY up, down, left, right and make the convergence to be optimal condition and stick rubber wedge to CPT so that the DY not to move.

Screen voltage adjustment
SCREEN manual adjust method (Used the remote controller)
(1) RF Mode, input the PAL or SECAM(NTSC) signal, every channel is OK.
(2) First LINE SVC MODE(IN-START KEY) and push the ADJ KEY change to the SCREEN adjustment MODE.
(3) Adjust the SCREEN VOL of the FBT, then TV picture will be have a horizontal line, manual adjust the FBT SCREEN VOL, when the horizontal line just disappear is OK.
(Press the TV/AV button to exit SVC mode)


Deflection setting Data Adjustment
Adjustment preparation
(1) TV set to receive an Digital pattern(PAL:E5ch.,NTSC: US-12).
(2) Deflection data setting used remote.
(3) Press the LINE SVC MODE(IN-START KEY) into SERVICE MENU, Choice SERVICE2 to adjustment mode.
(4) Press CH+,CH- KEY choice adjust item.
(5) Press VOL+,VOL - KEY increase or decrease DATA.
Adjustment
(1) First, adjust deflection at 50Hz,of PAL signal.  then, adjust deflection at 60Hz, of NTSC signal.
(2) Korea Model only used the N60Hz,adjustment . Adjust vertical inclination of screen.
(3) Central or South America Model first N60Hz adjustment and then N50(PAL-N) adjustment.
(4) When finish the adjustment and press “ENTER" KEY, save data and exit adjustment Mode.
Deflection adjustment small item
(1) V SLOPE
The cutting part(below) of picture transfer to Blanking.
Adjust the geometric vertical center of the CPT is in accord lower blanking.
(2) VS (Vertical Shift)
Adjust so that the horizontal center line of a digital circle pattern is in accord with geometric horizontal center of the CPT.

(3) VL (Vertical Linearity)
Adjust so that the boundary line between upper and lower half is in accord with geometric horizontal center of the CPT(PAL : E5ch., NTSC : US-13.).
(4) VA (Vertical Amplitude)
Adjust so that the circle of a digital circle pattern may be located within the effective screen of the CPT.
NTSC signal : Adjust NTSC 13CH circle as an inscribed circle of vertical outer boundary of the effective screen of the CPT.

(5) HS (Horizontal Shift)
Adjust so that the vertical center line of a digital circle pattern is in accord with geometric vertical center of the CPT 
(6) EW (Horizontal Width)
Adjust to that a digital circle pattern looks like exact circle.(PAL:0~25%,NTSC: 2.5~3.0

(7) EP (East-west Parabola)
Adjust so that middle portion of the outermost left and right vertical line looks like parallel with vertical lines of the CPT.
(8) ET (East-west Trapezium)
Adjust to make the length of top horizontal line same with it of the bottom horizontal line.
(8) ET (East-west Trapezium)
Adjust to make the length of top horizontal line same with it of the bottom horizontal line.
(9) EW UPCOR & EW LOCOR
Adjust until symmetries upper & lower corner of the screen.

(10) BOW
Adjust the left and right crooked line on upper and lower side.

11) H ANGLE
Adjust the vertical slope
(12) S CORRECT (S CORRECTION)
Adjust the receive Patter, keep the lattice's range same(Top/Center/Bottom. This decided by DY data, so according to the CPT's Default data(Initial data) Setting.

 (12) S CORRECT (S CORRECTION)
Adjust the receive Patter, keep the lattice's range same(Top/Center/Bottom)
This decided by DY data, so according to the CPT's Default data(Initial data) Setting.

(13) V SCROLL
Adjust the center vertical line of the geometrical with the CPT center vertical line same.
(14) V ZOOM (fixed) : VERTICAL ZOOM.
(15) WBR (fixed) : Timing of wide Blanking
(16) WBF (fixed) : Timing of wide Blanking
(17) V SYNSLI (fixed) : Vertical slicing level
(18) OVRVOLIN (fixed) : Over voltage input mode
(19)V GUARD (fixed) : Vertical guard mode

Initial data for deflection

Initial data for deflection by model (SERVICE 2)-PAL

Default data



Schematic diagram


No comments: