Chassis Service Adjustment Procedures; 131.0V B+ Voltage Confirmation; Source Voltage Chart; High Voltage Check - Panasonic CT-27D10B Service Manual

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 IC803's heat sink when the HOT ground
symbol ( ) is used. Otherwise, use COLD ground (
IC 001
IC 002
IC 6501
T T
U U
N N
E E
R R
FA1 CLK
TP
DATA TP15 FA2
MOMENTARILY CONNECT A JUMPER FOR ENTERING SERVICE MODE (FA1 to FA2 )

131.0V B+ Voltage Confirmation

1. Set the Bright and the Picture to Minimum by
using the Picture Menu.
2. Connect the DVM between C809(+ side) and cold
ground ( ).
3. Confirm that B+ voltage is 131.0V ± 2.5V. 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 ground
( ) for the (-) lead of the DVM.
LOCATION
TPD8
TPD9
C552 (+) side
IC551 Pin3
D554 Cathode
C572 (+) side
IC 003
SP
IC 551
IC 552
IC 2302
IC 101
IC 2361
IC 3001
VOLTAGE
27.4V ± 2V
13.0V ± 2V
8.0V ± 1V
9.0V ± 0.5V
220V ± 15V
5.0V ± 0.25V
) — Tuner shield, IC451's heat sink or FA2.
Figure 4. A-Board Main Components
COLD ( )
HOT ( )
RL801
IC 803
F801
TPD9
Adjust Picture Menu for normalized video adjustments.

High Voltage Check

1. Select an active TV channel and confirm that
horizontal is in sync.
2. Adjust Brightness and Picture using Picture Icon
menu so video just disappears.
3. Confirm B+ 131V is within limit.
4. Using a high voltage meter confirm that the High
Voltage is 28.30kV ± 1.25kV.
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IC451
Q 501
Q 551
TPD8 D554
C552
FOCUS SCREEN