SHARP 51GT25H
Manual de Servicio

51GT-25H

�PIF/AGC Adjustment
1. AFT Adjustment
AFT must be adjusted to a fixed value of 40.

�Screen Adjustment
3. Focus Adjustment 1. Apply mains voltage of 220V AC/50HZ to TV. 2. Receive Philips pattern signal to a level between
60 and 80 dBµV.

3. Set contrast to 10/10, brightness to 5/10 and
colour 0/10. 4. Adjust focus potentiometer to obtain maximum definition.

2. RF-AGC Cut-In Adjustment (I2C BUS) 1. Receive the «COLOUR BAR» signal (Channel E12). Signal strength: 57 dBµV.

4. G2 Adjustment 1. Apply mains voltage of 220V AC/50HZ to TV. 2. Receive the «MONOSCOPE» pattern signal to a
level between 60 and 80 dBµV. 3. Enter into Service Mode. Press the TEXT key of R/C and set to level.

2. Enter into Service Mode. 3. Push CH � until AGC appears on screen. 4. Push
key of R/C.Setting is made automatically. During this setting the colour bar shall go from red to yellow. When setting is finished, colour bar disappears and B-STOP (bus stop)is shown on screen.

4. Set to the point where the raster disappears on
the screen VR of FBT.

5. Check BKGD. If it is necessary adjust BKGD
according to instructions detailed in the next page.

5. Switch set OFF and ON again, setting is now
memorized.

�GEOMETRY ADJUSTMENT PROCEDURE
1. HOR SHIFT a) Receive Philips pattern signal. b) When � button is pressed, picture moves to the left. c) When � button is pressed, picture moves to the right. d) Adjust the horizontal location to obtain picture centering (Fig.1). 2. VERT SHIFT a) Receive Philips pattern signal. b) When � button is pressed, picture moves up. c) When � button is pressed, picture moves down. d) Adjust the vertical location to obtain picture centering (Fig.2). 3. VERT AM a) Receive Philips pattern signal. b) When � button is pressed, vertical size of picture increases. c) When � button is pressed, vertical size of picture decreases. d) Adjust the vertical size to obtain picture overscan (Fig.3). 4. VERT SLOP a) Receive Philips pattern signal. b) When � button is pressed, upper picture scanning decreases and lower picture scanning increases. c) When � button is pressed, upper picture scanning increases and lower picture scanning decreases. d) Adjust the vertical symmetry to obtain symmetrical scanning between upper and lower picture (Fig.4).
Fig. 4 Fig. 3 Fig. 2 Fig. 1

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