SHARP 37GT25H
Service Manual

37GT-25H

�GEOMETRY ADJUSTMENT PROCEDURE
1. HOR POS 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 POS 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). 3. 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

�COLOUR ADJUSTMENT PROCEDURES
1. Y-DLY a) Receive Philips pattern signal. b) When � button is pressed, luma phase delays. c) When � button is pressed, chroma phase delays. d) Adjust the chroma-luma delay. 2. «B-GAIN», «G-GAIN», «R-GAIN» a) Adjust G2. b) Tune a white pattern c) Adjust colour to minimum. d) Position colourmeter in the center of screen. e) Using brightness and contrast buttons, select a luminance of �120 nits. f) Operate again in Service Mode and select location R-GAIN and B-GAIN to obtain colour coordinates: X = 0.290 ± 0.015 Y = 0.284 ± 0.015 g) Exit Service Mode and check colour coordinates «X» and «Y» at 20 and 120 nits. It may be necessary to repeat the same procedure or re-adjust the cuts as show the be below one.
NOTE: Locations «R» alter «X» coordinates; «G» alter «Y» coordinates; «B» alter «X» and «Y» coordinates.

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