KV-27V42 - Sony TV Service Manual (repair manual). Page 17

The following adjustments should always be performed when
replacing the following components which are marked with

 on the schematic diagram.

DY, C511, C573, C574, C575, D572, D573, D574,
R582, R583, R585, R586, R578, R625, R626, T504, IC301,
IC521, IC602, C507, C508, C505, C509, C515, C520, L591,
L501

1. Using a Variac, apply AC input voltage: 120 ± 2 VAC

(or 120-220 ± 2 VAC for KV-29SL42K).

2. Turn the POWER switch ON.

3. Input an entirely white signal and set the PICTURE and

BRIGHTNESS controls to maximum.

4. Confirm that the voltage between C574 (+) or TP503

and ground is more than 105 VDC.

1. Connect the current meter between Pin 11 of the FBT

(T504) and the PCB land where Pin 11 would normally
attach. (See Figure 1 on the following page.)

2. Input a dot signal and set PICTURE and BRIGHTNESS

to minimum: IABL = 100 + 100/-95

mA.

3. Confirm the voltage of A Board TP-600 is

135 ± 3 VDC.

4. Connect the digital voltmeter and the DC power supply

via diode 1SS119 to C574 (+) and ground.
(See Figure 1 on the following page.)

5. Increase the DC power voltage gradually until the picture

blanks out.

6. Read the digital voltmeter indication.

(standard: less than or equal to 141.3 VDC).

7. Turn DC power source off immediately

8. Input a white signal and set PICTURE and BRIGHTNESS

to maximum.

9. Repeat steps 4 to 7.

If the setting indicated in step 2 of Hold-down Operation
Confirmation cannot be met, readjustment should be performed
by altering the resistance value of R584, a component marked
with 

 .

+

I  ABL

ABL

FBT

Range

-

Ammeter

3.0 mA DC

A

Note: The following adjustments should always be performed
when replacing the following components, which are marked
with   on the schematic diagram.

IC601, IC602

1. Using a Variac, apply AC input voltage: 130 ± 2 VAC

(or 120-220 ± 2 VAC for KV-29SL42K).

2. Input a dot signal.

3. Set the PICTURE and BRIGHTNESS controls to minimum.

4. Set to Service Adjustment Mode.

5. Select PADJ with 

 and 

.

6. Adjust with 

 to the 0 level.

7. Confirm the voltage of A board TP-600 is less than

138 VDC.

8. If step 7 is not satisifed, replace the components and repeat

the above steps.

9. Supply 120 ± 2 VAC (or 120-220 ± 2 VAC for KV-

29SL42K)  to the set with a variable auto transformer.

10. Adjust with 

 and 

 for 135 ± 3 VDC.

11. Press 

 then 

 to save into the memory.

T504