Safety Related Adjustments 0 - Sony Trinitron KV-27EXR95 Service Manual

Test Equipment Required.
Note:
1. Ammeter
2. DC Power Supply
3. Digital multimeter
Audio OSC
4.
5. Valiable auto-transformer
ABOARDANDCBOARD
CONFIRMATION) AND READJUSTMENTS
The following adjustments should always be per-
formed when replacing the following components
(marked with 0 on the schematic diagram).
A BOARD : PM501,Q608,Q607,R629,R628,R627,R559
1. Preparation before confirmation
1) Remove R675 on the G board and connect a
variable resistor (RVl : about 10kfi ) between
pin 0 of IC653 and B+ line.
2) Supply 120+2.OV AC to with variable auto-
transformer.
2. Hold-down operation confirmation
1) Turn the POWER switch ON, and input an
entirely white signals and adjust ABL current to
1650 +80 PA with PICTURE and BRIGHT etc
controls.
2) Increase B+ line voltage gradually by adjusting
the resistor of RVl. Confirm that the minimum
voltage is less than 143.5V
raster disappears during operation of hold-down
circuit.
When the hold-down circuit starts
NOTE:
operating, switch OF'F the POWER of
the set immediately.
3) Turn the POWER switch ON, and input a dot
signals and adjust ABL current to 150+50pA
with PICTURE and BRIGHT etc controls.
4) Increase B+ line voltage gradually by adjusting
the resistor of RVl. Confirm that the minimum
voltage is less than 146.5V
raster disappears during operation of hold-down
circuit.
When the hold-down circuit starts
NOTE:
operating, switch OFF the POWER of
the set immediately.
SECTION 4

SAFETY RELATED ADJUSTMENTS 0

DC whereby the
DC whereby the
3. Hold-down readjustment
When step 2 is not satisfied, readjustment should
be performed by altering the resistance value of
R559 (a component marked with
q
>. T500;