Set-Up Adjustments; Screen Voltage Adjustment (Coarse Adjustment); Screen (G2) Adjustment (Fine Adjustment); Deflection York Tilt Adjustment - Sony KP 48S75 Service Manual

KP-43T75/48S75/
53N77/53S75/61S75
RM-Y906
3-1. SCREEN VOLTAGE ADJUSTMENT
(COARSE ADJUSTMENT)
1. Receive the Monoscope signal.
2. Set 50% BRIGHTNESS and minimum PICTURE.
3. Turn the red VR on the FOCUS block all the way to the left
and then gradually turn it to the right until the point where you
can see the retrace line.
4. Next gradually turn it to the left to the position where the
retrace line disappears.
R G
SCREEN
R G
FOCUS
FOCUS block
3-2. SCREEN (G2) ADJUSTMENT
(FINE ADJUSTMENT)
Fine Mode is recommended to set screen controls to their optimal
condition. It is necessary to build the simple jig, illustrated below,
using 3-watt resistors. Please note, that if the proper voltage is not
obtained with their listed values, resistors, then please increase or
decrease one of the values in the resistor network to obtain the
correct voltage.
1. Select VIDEO1 mode without signals.
2. Connect G2 JIG.
3. SW on JIG.
4. Connect an oscilloscope to the TP701(KR), TP732(KG) and
TP761(KB) of CR board, CG board and CB board.
5. Adjust R, G and B screen voltage to 170-173V with screen
VR on the Focus block.
G2 JIG
3.3k
200V
GND
3-3. DEFLECTION YOKE TILT ADJUSTMENT
1. Receive the Monoscope signal.
2. Set in service mode.
3. Cover the both red and blue picture lenses with the lens caps
to show only the green color.
4. Loosen the deflection yoke set screw and align the tilt of the
Deflection Yoke so that the bars at the center of the
monoscope pattern are horizontal.
5. After aligning the deflection yoke, fasten it securely to the
funnel-shaped portion (neck) of the CRT.
6. The tilt of the deflection yoke for red is aligned in the mode
Cover the both green and blue picture lenses with the lens caps
and the tilt of the deflection yoke for blue is aligned with in

SET-UP ADJUSTMENTS

B
B
Fig. 3-1
K
SW
5.6k 5.6k 5.6k
GND
pedestal level
175 2V
Fig. 3-2
SECTION 3
the mode Cover the both green and red picture lenses with the
lens caps is aligned the same as was done for green.
Note: Instead of items 3 and 6, you can cut off the unnecessary
color beams by controlling the service mode VPNT 28 RON,
29 GON, and 30 BON.
2-pole magnet
Fig. 3-3

3-4. FOCUS LENS ADJUSTMENT

In this adjustment, use the remote commander in the
service mode.
For details of the usage of the service mode and the remote
commander, please refer the item 3-9. ELECTRICAL
ADJUSTMENT BY REMOTE COMMANDER.
1. Loosen the lens screw.
2. Set to the service mode.
3. Receive the all-white signal.
4. Cover the both red and blue picture lenses with the lens caps
to show only the green color.
5. Set to PJE, and press 6 to display the test signal (crosshatch)"
on the screen.
6. Turn the green lens to adjust to the optimum focus point with
the test signal.
7. Tighten the lens screw.
8. Cover the both green and blue picture lenses with the lens caps
to show only the red color.
9. Set to PJE, and press 6 to display the test signal (crosshatch)"
on the screen.
10. Adjust red CRT lens just the same as green.
11. Cover the both green and red picture lenses with the lens caps
to show only the blue color.
Test signal
12. Set to PJE, and press 6 to display the test signal (crosshatch)"
on the screen.
13. Adjust blue CRT lens just the same as green.
14. After adjusting the items 3-5. Focus VR Adjustment, 3-6. 2-
Pole Magnet Adjustment and 3-7. 4-Pole Magnet Adjustment,
adjust again to the optimum focus point.
*: Every time you press 6, the test signal changes to
"crosshatch+video signal" - "dots+video signal" -
"crosshach(black)" - "dots(black)" - off.
Note: Instead of items 4, 8 and 11, you can cut off the unnecessary
color beams by controlling the service mode VPNT 28 RON,
29 GON, and 30 BON.
– 36 –
4-pole magnet
Deflection yoke
Anode cap
Fig. 3-4