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Chassis Service Adjustment Procedures
All service adjustments are factory preset and should not require adjustment unless controls and/or
associated components are replaced.
Note: Connect the (-) lead of the voltmeter to the appropriate ground. Use IC801’s heat sink when the HOT ground
symbol ( ) is used. Otherwise, use COLD ground (
) — Tuner shield, IC451’s heat sink or FA2(TP-3).(See Fig. 8)
140.0V B+ Voltage Confirmation
1.
Set the Bright, Picture and Color to Minimum by
using the Picture Menu.
2.
Connect the DVM between C849, + side (A-Board)
and cold ground (
).
3.
Confirm that B+ voltage is 140.0V ± 1.5V. This
voltage supplies B+ to the Horizontal Output &
Flyback circuits.
Source Voltage Chart
120V AC line input. Set the Bright and the Picture to
Minimum by using the Picture Menu. Use cold
(
) or
Hot ( ) ground for the (-) lead of the DVM as needed.
Set all adjustments to normal level.
C563
F801
T
U
N
E
R
TP
1
8
C6501
TPD72
TPA143
C038
C837
TPD76
TPA146
C849
Q551
IC
101
IC891
IC882
MPU
IC001
COMB FILTER
IC6501
D841
A11
T801
HOT GND ( )
COLD GND ( )
DY
IC451
Q451
LOCATION
(A-Board)
VOLTAGE
TPD72
24
± 2 V DC
C837 (+)
13.0
± 2 V DC
TPA143
9.0
±1 V DC
TPD76
12.0
± 0.5 V DC
TPA146
5.0
± 0.25 V DC
C6501 (+)
5.0
± 0.25 V DC
C038 (+)
3.3
± 0.1 V DC
