Read Sony KV-29AL40 Service Manual online
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17
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KV-29AL40/KV-29AL40A/KV-29AL40C
A
BOARD
The following adjustments should always be performed when
replacing the following components which are marked with
] on
the schematic diagram:
DY, C511, C572, C573, C574, C575, D573, D574, R582, R583,
R585, R586, R578, R579, T504, IC301, IC521, IC603, C507,
C508, C509, C515, C520, L591, L501
R585, R586, R578, R579, T504, IC301, IC521, IC603, C507,
C508, C509, C515, C520, L591, L501
(1)
Preparation before Confirmation
Using Variac, apply AC input voltage: 120+2VAC
(or 220 + 2 VAC for KV-29AL40A/C)
(or 220 + 2 VAC for KV-29AL40A/C)
1)
Turn the POWER switch ON.
2)
Input a white signal and set the PICTURE and BRIGHT
controls to maximum.
controls to maximum.
3)
Confirm that the voltage between C574 (+) or TP503 and
ground is more than: 105VDC.
ground is more than: 105VDC.
(2)
Hold-down Operation Confirmation
1)
Connect the current meter between Pin 11 of the FBT
(T504) and the PCB land where Pin
(T504) and the PCB land where Pin
11
would normally
attach. (see figure 1.0 on next page)
2)
Input a dot signal and set PICTURE and BRIGHTNESS to
minimum: IABL = 100+100µA
minimum: IABL = 100+100µA
3)
Confirm the voltage of A board TP-600 is 135 ± 3VDC
4)
Connect the Digital Voltmeter and the DC power supply
via diode 1SS119 to C574 (+). (See figure 1.0 on next
page.)
via diode 1SS119 to C574 (+). (See figure 1.0 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
Less than or equal to:
Less than or equal to:
141.3 VDC
8)
Input a white signal and set PICTURE and BRIGHTNESS
to maximum: IABL = 1750+100µA
to maximum: IABL = 1750+100µA
9)
Repeat steps from (4) to (7).
STANDARD
Less than or equal to:
Less than or equal to:
141.3 VDC
SECTION 4
SAFETY RELATED ADJUSTMENTS
The following adjustments should always be performed
when replacing the following components which are
marked with
] on the schematic diagram:
IC603, IC601, R699
1)
Using Variac, apply AC input voltage: 130 + 2.0 VAC
(or 220.0 ± 2.0 VAC for KV-29AL40A/C).
(or 220.0 ± 2.0 VAC for KV-29AL40A/C).
2)
Input a dot signal.
3)
Set the PICTURE control and the BRIGHT control 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 satisfied, replace the components, repeat
the above steps.
9)
Adjust with and
for:
135 ± 3 VDC
10) Write into the memory by pressing
then
.
B+ VOLTAGE CONFIRMATION AND ADJUSTMENT
(3)
Hold-down Readjustment
If the current setting indicated in step 2-2 cannot be met,
readjustment should be performed by altering the resistance
value of R584, a component marked with
value of R584, a component marked with
.
+
I ABL
ABL
T504
FBT
range
-
ammeter
3.0 mA DC
A
R584 CONFIRMATION METHOD (HV HOLD-DOWN CONFIRMATION) AND READJUSTMENTS
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