Sony FD Trinitron WEGA KV-36FS12, Service Manual

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KV-36FS12/36FS16/36FV16/36FV26
Preparation before Confirmation
1. Using a Variac, apply AC input voltage: 130+2.0/-0.0 VAC.
2. Turn the POWER switch ON.
3. Input a white signal and set the PICTURE and BRIGHT
controls to maximum.
4. Confirm that the voltage of more than 23.0 VDC appears
between TP85 and ground on the A Board.
Hold-Down Operation Confirmation
1. Connect the current meter between Pin 11 of the FBT
(T503) and the PWB land where Pin 11 would normally
attach (See Figure 1 above).
2. Input a dot signal and set PICTURE and BRIGHTNESS
to minimum: IABL = 2175 + 100/ -325 µA.
3. Confirm the voltage of A Board TP91 is 135 ± 1.5 VDC.
4. Connect the digital voltmeter and the DC power supply to
TP85 and ground. (See Figure 1 above).
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 = 27.24 + 0.0/ - 0.1 VDC).
8. Input a white signal and set PICTURE and BRIGHTNESS
to maximum: IABL = 2175 + 100/ -325 µA.
9. Repeat steps 4 to 7.
SECTION 4
SAFETY RELATED ADJUSTMENTS
4-1. R530, R531 CONFIRMATION METHOD
(HOLD-DOWN CONFIRMATION) AND
READJUSTMENTS
Always perform the following adjustments when replacing the
following components marked with a
mark on the schematic
diagram:
Hold-Down Readjustment
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 R530, R531 component
marked with
.
Figure 1
3mA DC range
+
-
+
-
A
+
-
11
T503
FBT
TP85
T503
FBT
TP85
R531
R530
DC Power Supply
digital multimeter
ammeter
4-2. B+ VOLTAGE CONFIRMATION AND
ADJUSTMENT
Note: The following adjustments should always be performed
when replacing the following components, which are marked
with on the schematic diagram on the G Board.
G BOARD:
IC643, R661
1. Using a Variac, apply AC input voltage: 130 + 2.0/-0.0 VAC
2. Input a monoscope signal.
3. Set the PICTURE control and the BRIGHT control to
initial reset value.
4. Confirm the voltage of G Board CN641 between
pin to ground is less than 136.5 VDC.
5. If step 4 is not satisfied, replace the R661and repeat the
above steps.
Part Replaced ( ) Adjustment ( )
R387, R550, R529, R530, R531,
R532, R533, D519, D520, D521,
IC501, C531, C532, T503, IC351,
IC355, Q301, R356, R359, R361,
D302 ............................... A Board
IC643, R661 .................. G Board
HV HOLD-DOWN
R530, R531