Safety Related Adjustments; R564 Confirmation Method (Hv Hold-Down Confirmation) And Readjustments; B+ Voltage Confirmation And Adjustment - Sony TRINITRON KV-29FS12K Service Manual

KV-29FS12K
3-1. R564 CONFIRMATION METHOD
(HV HOLD-DOWN CONFIRMATION) AND
READJUSTMENTS
The following adjustments should always be performed when
replacing the following components which are marked with
the schematic diagram:
Part Replaced ( )
DY, T505, CRT, IC501, C507,
C520, C505, C509, C515, T504,
T503, C551, L510, C546, C537,
C547, D517, D518, D519, R560,
R561, R562, R563, R565, R566,
R567, R525 ....................... A Board
IC301 .............................. MA Board
Preparation Before Confirmation
1. Using a Variac, apply AC input voltage: 120 ± 2 VAC.
2. Turn the POWER switch ON.
3. Input a white signal and set the PICTURE and
BRIGHTNESS controls to maximum.
4. Confirm that the voltage between C546 (+) or TP503
and ground is more than 21.0 VDC.
Hold-Down Operation Confirmation
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 the next page.)
2. Input a dot signal and set PICTURE and BRIGHTNESS
to minimum: IABL = 1730 ± 100 µA.
3. Confirm the voltage of A Board TP-600 is 135 ± 1.5 VDC.
4. Connect the digital voltmeter and the DC power supply
via diode 1SS119 to C546 (+) and ground. (See Figure 1
on the 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 < 24.78+0,-0.1 VDC).
8. Input a white signal and set PICTURE and BRIGHTNESS to
maximum: IABL = 1730 ± 100 µA.
9. Repeat Steps 4 to 7.
SECTION 3

SAFETY RELATED ADJUSTMENTS

on
Adjustment ( )
HV HOLD-DOWN
R564
— 14 —
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 R564 component marked with
3-2. 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 A Board.
A BOARD: IC601, PH601
1. Using a Variac, apply AC input voltage: 130 + 2.0, -0.0 VAC.
2. Input a dot signal.
3. Set the PICTURE and BRIGHTNESS controls to minimum.
4. Confirm that the voltage of A Board TP-600 is <136.5 VDC.
5. If Step 3 is not satisfied, replace the components listed above,
then repeat Steps 1–3.
.
T505
FBT
ammeter
3.0 mA DC
range
ABL
-
+
A
IABL