KV-21FS105 (serv.man2) - Sony TV Service Manual (repair manual). Page 14

3-1.  X R562 CONFIRMATION METHOD 

Always perform the following adjustments when replacing the following 
components marked with a Y mark on the schematic diagram:

Part Replaced (     )

Adjustment (     )

HV HOLD-DOWN
(R562)

DY, T505, CRT, IC1301, IC501, C507,
C520, C505, C509, C515, T504,
L508, C551, L510, C546, C537, 
C547, D517, D518, D519, R560,
R561, R562, R563, R565, R566, 
R567, R525........................A Board

1.  Using a Variac, apply AC input voltage: 120-220 +/- 2.0 VAC.

2.  Turn the POWER switch ON.

3.  Input a white signal and set the PICTURE and BRIGHTNESS 

controls to maximum.

4.  Confi rm that the voltage of more than 97 VDC appears between 

C546(+) or TP503 and ground on the A Board. 

1.  Connect the current meter between Pin 11 of the FBT (T505) and the 

PWB land where Pin 11 would normally attach. 
(See Figure 1 on next page).

2.  Input a dot signal and set PICTURE and BRIGHTNESS to minimum: 

IABL = 100 ± 100 µA.

3.  Confi rm the voltage of A Board TP600 is 135 ± 1 VDC.

4.  Connect the digital voltmeter and the DC power supply via diode 

1SS119 to C546 (+) and ground. 
(See Figure 1 on next page).

5.  Increase the DC power voltage gradually until the picture blanks out.

6.  Turn DC power source off immediately.

7.  Read the digital voltmeter indication (standard = 115.7 VDC).

8.  Input a white signal and set PICTURE and BRIGHTNESS to 

maximum: IABL = 1350 ± 100 µA.

9.  Repeat steps 4 to 7.

If the setting indicated in Step 2 of Hold-Down Operation Confi rmation 
cannot be met, readjustment should be performed by altering the 
resistance value of the R562 component marked with X. 

+

IABL

ABL

T505

FBT

range

-

ammeter

3.0 mA DC

A

Always perform the following adjustments when replacing the components 
which are marked with Y on the schematic diagram on the A Board:

     A BOARD:   IC601, PH601 

1.  Using a Variac, apply AC input voltage: 130 ± 2.0 VAC

2.  Input a dot signal.

3.  Set the PICTURE control and the BRIGHTNESS control to minimum.

4.  Confi rm the voltage on A Board between TP-600 and ground is less 

than 136 VDC.

5.  If step 4 is not satisfi ed, replace the components on A Board listed 

above, and then repeat the steps 1-4.