Safety Related Adjustments - Sony TRINITRON KV-20TS29 Service Manual

KV-20TS29/20TS32
KV-21STR2/2170RS
RM-Y116
SECTION 4
SAFETY RELATED ADJUSTMENTS
A BOARD
b4 R537 CONFIRMATION METHOD (HV HOLD-
DOWN CONFIRMATION) AND READJUSTMENTS
The following adjustments should always be per-
formed when replacing the following components
(marked with [@ on the schematic diagram).
IC602, D511, C523, C524, R534, R535, R537, R549,
R565, R637, PM501, T504, DY
®
1. Preparation before confirmation
1) Turn the POWER switch ON, and receive
entirely white signal and set the PICTURE and
BRIGHT controls to maximum.
2) Confirm that the voltage of the check terminal of
TP85 is more than 100VDC when the set is
operating normaly with 120.0+2.0VAC supply.
2. Hold-down operation confirmation (HV)
1) Connect the currentmeter between the 7th pin of
FBT (T504)and the land of it with connect
polarity.
2) Receive White Signal ana adjust the ABL
current to follows with the PICTURE and the
BRIGHT controls.
1450 + 100nA
Connect the Digital Voltmeter to pin8 of PM501
then read the voltage as A.
Connect the Digital Voltmeter and DC power
Supply via 18S 119 to TP-85.
5) Increase the DC power voltage gradually until
the Picture just blanks out.
6) Read the digital volymeter indication.
7) Turn DC power Source off immediatery.
STANDARD
Less or equal to A + 16.5 VDC
8) Receive Dot Signal and adjust the ABL current
to follows, with the PIX and the BRT controls.
150 + 100pA
9) Repeat steps from (3) to (7).
STANDARD
Less or equalto A + 16.5 VDC
—
3
~~
4
~~
3. Hold-down readjustment
When step 2 is not satisfied, readjustment should
be performed by altering the resistance value of
R537 (a component marked with BA).
T504
FBT
§e emewunnceneene
A BOARD
B4 R511 CONFIRMATION METHOD (B+ HOLD-
DOWN CONFIRMATION) AND READJUSTMENTS
The following adjustments should always be per-
formed when replacing the following components
(marked with [@ on the schematic diagram).
IC602, C524, R511, R534, R549, R565, R637, PM501
@
1. Hold-Down Operation Voltage (B+)
1) Connect the currentmeter between the 7th pin of
FBT (T504)and the land of it with connect
polarity.
. 2) Receive White Signal and adjust the ABL
current to follows with the PICTURE and the
BRIGHT controls.
1450 + 100pA
3) Connect the Digital Voltmeter and DC power
Supply via 1SS 119 to pin8 of PM501.
4) Increase the DC power voltage gradually until
the Picture just blanks out.
5) Read the digital voltmeter indication.
6) Turn DC power Source off immediatery.
STANDARD
Less or equal to 130.0 VDC
7) Receive Dot Signal and adjust the ABL current
to follows, with the PICTURE and the BRIGHT
controls.
150 + 100pnA
Repeat steps from (4) to (6).
STANDARD
Less or equal to 132.5 VDC
8
—
N
. Hold-down readjustment
When step 2 is not satisfied, readjustment should be
performed by altering the resistance value of R511 (a
component marked with B4).
G BOARD
B+ VOLTAGE CONFIRMATION
The following adjustments should always be perform-
ed when replacing IC602 or R637.
1) Supply 130+%°V AC to with variable autotrans-
former.
2) Input an entirely monoscope signal.
3) Set the PICTURE control and the BRIGHT
controls in to initial reset.
4) Confirm the voltage of A BOARD @) pin CN651
connecter is less than 116.5V DC.
5) If step 4) is not satisfied, replace IC602 and R637
repeat above steps.
2246