Sharp 37GT-25S, Service Manual

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10
37GT-25S
Fig. 4
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).
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).
•
GEOMETRY ADJUSTMENT PROCEDURE
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).
Fig. 2
Fig. 1
4. VERT SLOP
Fig. 3
a) Receive Philips pattern signal.
b) When
∧
button is pressed, upper picture scanning decreases and
lower picture scanning increases.
••••• PIF/AGC Adjustment
••••• Screen Adjustment
3. Focus Adjustment
Set contrast to 10/10, brightness to 5/10 and
colour 0/10.
Apply mains voltage of 220V AC/50HZ to TV. 1.
Receive Philips pattern signal to a level between
60 and 80 dB
µ
V.
2
.
3
.
Adjust focus potentiometer to obtain
maximum definition.
4
.
1. AFT Adjustment
AFT must be adjusted to a fixed value of 40.
Receive the «COLOUR BAR» signal (Channel E-
12).
Signal strength: 53 dB
µ
V.
2. RF-AGC Cut-In Adjustment (I2C BUS)
Switch set OFF and ON again, setting is now
memorized.
1
.
Enter into Service Mode.
2
.
Push CH
∧
until AGC appears on screen.
3
.
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.
5
.
4. G2 Adjustment
the screen VR of FBT.
5
.
Check BKGD. If it is necessary adjust BKGD
according to instructions detailed in the next
page.
Apply mains voltage of 220V AC/50HZ to TV.
1.
Receive the «MONOSCOPE» pattern signal to a
level between 60 and 80 dB
µ
V.
2
.
3
.
4
.
Enter into Service Mode. Press the TEXT key of
R/C and set to level.
Set to the point where the raster disappears on