Panoramic TVP-2905AS, Service Manual

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Service Adjustments
-16-
VOL + VOL -
CH + MENU
VOL + VOL -
CH + CH -
2
1
T4AL250V
VOL + VOL -
CH + CH - MENU
W601
E
E
E
E
E
1
2
4
3
E
E
R/G
16
10
71
1
7 81
4
PS601A
JP601
RL601
KE-2
KE-1
KE
D641
R620
F601A
F601B
R602-H1
SW190
SW1902
SW1905 SW1904 SW1903
KH
R602-H4
R602B
R602-H2
R602
R601
L601
C601A
C601
C606
C605
C608
D606
D605
D608
SW601-H4
SW601-H2
KG-1 KG-2
VA601
D607
D1902
J032
C610
R103
435
D
C468
R445
R652
C651
C609
Q612
R643
R642
R641
R624
R623
R622
R619
R616
R614
R613
R611
Q642
Q641
Q625
Q611
D616
C611 R633
C614
D615
D614
R615
D610
L612
D643
D611
L613
R627
D619
R631
D617
L616
R4
R628
R629
C629
C628
D652
C654
R653
C657
R665
R664
C693
Q693
C658
C613
R621
R625 R626
Q613-H6
Q613
C615
L615
R632
L614
R644
C644
C639
C656
L651
L653
C655
D651
D654
R661
C617
J010
J012
D469A
J
C6
J060
J061
J062
J063
J064
C66
J065
D661
R663
R695
L654
Q691
J069
J079
JP652
R662
L601-H2
L601-H1
L601-H4 L601-H3
C609-H1
J142
J009
J144
J14
R435H1
C618
D653
R1907
D1901
C652
R602A
PS601
R602-H3
R602-H5
R602-H6
R602-H7
R602-H8
JP488
R650
D650
D639
R639
C609-H2
A1901
C1902
VR651
J135
T611A
T611B
J165
TP-B
CONVERTER
TRANS.
+B ADJ.
TP +B +130V
E
B
33
T471-H1 T471-H2
T471-H4
T471-H5
T471-H6
T471-H7
T471-H10
T471
D485
R488
R481
C423
C423-H1
C423-H2
C423-H3
D438
C420
C420-H1
C420-H2
C
420-H3
C423A
C420B
C424A
C424
D439
C422
C422A
JP436
L431
C425
C425A
KQ
C486
C471
C442A
L442
431
R485
C424-H1
C425-H1
C424-H3 C425-H3
KDY-1
C442-
C442-H3
C442-H1
C
L462H2
C
42
0A
C420A-H2
T471-H9
1 4
KDY
T471A
Q432-H5
Q432-H4
Q432-H2
Q432
T471-H8
Q432-H3
Q432-H1
C487
1A
JP487
JP486
C486A
T471-H11
T471-H3
R487
C420A-H1
(FBT)
H-OUT
C
Service Adjustment-4
Note: +B (+130V) Voltage and Grayscale Adjustment must
be completed before attempting High Voltage Check.
1. Connect high voltage voltmeter negative lead to
ground, and c lead to anode of picture tube.
2. Tune receiver to an active channel and confirm TV is
operating properly.
3. The high voltage must be 28.5KV ± 1KV and less than
32KV at 0 beam current (Brightness and contrast
minimum setting).
Note: If the picture tube is replaced, check the high
voltage.
HIGH VOLTAGE CHECK
FOCUS VR (Upper side)
This TV set has a built-in power supply protection circuit.
It is provided to protect the TV set in case of a power
supply circuit malfunctions. When something abnormality
occurs during TV reception, the TV set goes to the stand-
by mode.
When an abnormality occurs during TV reception, it
causes pin 27 of the CPU to go continually Low volt-
age for about one second. The CPU detects that this
has occurred and outputs the signal from pin 31 to
switch off the power supply lines.
Releasing the protective circuit and restor-
ing power supply
To release the protective circuit and restore power supply,
turn the power to the TV set OFF and then ON again via
either the main power switch or the ON-OFF button on the
remote control. This will work only if the power supply trou-
ble was temporary. If there is permanent trouble such as a
damaged circuit, power cannot be restored and the circuit
will have to be repaired.
Protection Circuit
F.B.T.
VR651
TP +B +130V
1. Receive the monochrome circular pattern.
2. Set the brightness to normal and contrast to maximum.
3. Adjust the focus control on the F.B.T. for the best focus
on the screen centre.
FOCUS ADJUSTMENT
1. Connect a DC voltmetre to TP-”+B +130V” and the
ground. Set the +B adjustment control (VR651) to
middle range.
2. Set the brightness to normal and contrast to maximum.
3. Tune the receiver to an active channel and synchro-
nized picture.
4. B voltage to 130± 0.5 volt DC by using VR651.
+B POWER SUPPLY ADJUSTMENT