Safety Related Adjustment - Sony TRINITRON PVM-2950QM Service Manual

PVM-2950Q/2950QM
RM-854
SECTION 4
SAFETY RELATED ADJUSTMENTS
\ CONFIRMATION OF HOLD-DOWN(
8
R583) \
Be sure to carry out the following adjustments after replacing the
following parts (indicated with a [.;ii sign in the circuit chart).
[.;ii
C574, D515, IC501, IC620, Q517, Q518, R578, R580, R581,
R582,R583,R584,R585, T504
(1) Confirmation of B + line.
I. Input a voltage of 130:': %·.&v AC and set picture and
brightness to minimum level.
2. Confirm that the voltage on the B+ line is 135. 6VDC or less
when receving the dot signal.
(2) Confirmation of hold-down operation
I. Set the power source voltage to AC120Yand receive the
all-white signal.
2. Adjust the picture and the brightness
so that IABL is 1610
±
50 µA.
3. Confirm that the hold-down circuit operates and the raster
disappears at a voltage of DC 147.3V or less when applying
voltage from external DC power source to the cg) pin of
ICSO!.
R573
IC501 (PM-30) @pin. ____ .......,
L512
C512
I
T501
FBT
I
ammeter
1
3.0mA de
1
range
--...--0-~+--1 A
---o-~
ABL-
1 ABL
I
I
I
I
I
I
I
I
I
_J
(US, Canadian Model)
\ CONFIRMATION OF HOLD-DOWN(
8
R581) \
Be sure to carry out the following adjustments after replacing the
following parts (indicated with a [.;ii sign in the circuit chart).
[.;ii
C574, D515, IC501, IC620, Q517, Q518, R578, R580, R581,
R582,R583,R584,R585, T504
(1) Tertiary winding detection
1. Set the power source votage to A Cl 20V
and receive the all-white signal.
2. Adjust the picture and brightness so that IABL is 1610
±
50
µA.
3. Confirm that the hold-down circuit operates and the raster
disappears at a voltage of DCl47.9V or less when applying
voltage from the external DC power source to the @ pin of
ICS0lon substrate A.
!CONFIRMING THE +B VOLTAGE
I
The following confirmations must be carried out when replacing
IC620.
I. Input A Cl 30 :': %·.& V 60 Hz as the input voltage to the power
source section.
2. Receive the dot signal and set CONT and BRT to MIN. At this
time the voltage on the +Bline should be 135. 6 V or less.
digital
multimeter
(AEP, AUS Model)
- 27 -
PVM-2950Q/2950QM
digital
multimeter
RM-854
- 28 -
regulated-de
power supply
~µ
digital
multimeter
ammeter
3m A de ramge