Panasonic TX-25P80T Service Manual ▷ View online
5.6. PAL COLOUR OUTPUT
Item/Preparation
Adjustment Procedure
1.
Receive PAL colour bar pattern.
2.
Connect an oscilloscope probe to TPA40.
3.
Connect a short jumper to FBT pin 3 or TPA34 and TPA32.
4.
Set control :
Picture menu.....................DYNA MIC NORMAL
AI................ .................... ..off (for model with AI only)
AI................ .................... ..off (for model with AI only)
1.
Adjust Bright Control.
a = 2.3±-0.2Vp-p
2.
Adjust Sub Colour control.
3.
Connect the osciloscope probe to TPA40.
4.
Connect the waveform.
b = 3.1±-0.5Vp-p
5.7. NTSC COLOUR OUTPUT
Item/Preparation
Adjustment Procedure
1.
Apply 3.58MHz NTSC Rainbow pattern.
2.
Connect an oscilloscope to TPA40.
3.
Connect a short jumper to FBT pin 3 or TPA34 and TPA32.
4.
Set control :
Picture menu.......................DYN AMIC CONTROL
Channel Colour Set...........ST D
1.
Adjust Bright Control.
a = 2.3±-0.2Vp-p
2.
Connect the waveform.
b = 1.3±-0.5Vp-p
9
TX-25P80T
5.8. COLOUR PURITY
1. Set Bright and Contrast controls to their maximum
positions.
2. Operate the TV set over 15 minutes.
3. Full degauss the picture tube by using an external
3. Full degauss the picture tube by using an external
degaussing coil. By rotating R-B static convergence
magnet.
magnet.
4. Apply a crosshatch pattern signal and adjust roughly the
static convergence magnets.
5. Apply a green pattern signal.
6. Loosen a clamp screw for the deflection yoke and move the
6. Loosen a clamp screw for the deflection yoke and move the
deflection yoke as close to the purity magnet as possible.
7. Adjust the purity magnet so that a vertical green field is
obtained at the center of the screen.
8. Slowly press the deflection yoke and set it where a uniform
green field is obtained.
9. Adjust roughly the Low Light controls and make sure that a
uniform white field is obtained.
10. Tighten the clamp screw.
5.9. CONVERGENCE
1. Apply a crosshatch pattern signal and set Contrast control
to the maximum position.
2. Adjust Bright control to obtain a clear pattern.
3. Adjust Red and Blue line at center of the screen.
3. Adjust Red and Blue line at center of the screen.
4. Adjust Red and Blue with Green line at center of the screen
by rotating (RB)-G static convergence magnet.
5. Lock convergence magnets with silicone sealer.
6. Remove the DY wedges and slightly tilt the deflection yoke
6. Remove the DY wedges and slightly tilt the deflection yoke
vertically.
7. Fix the deflection yoke by re-inserting the DY wedges.
8. If purity error is found, repeat “Colour Purity” adjustment.
8. If purity error is found, repeat “Colour Purity” adjustment.
Before Colour Purity, Convergence and White Balance adjustments are attempted, V. Center, V. Height, H. Width, H. Center and Focus
adjustments must be completed.
adjustments must be completed.
10
TX-25P80T
Preparation
1. Receive a colour bar signal with colour “OFF”, and operate
1. Receive a colour bar signal with colour “OFF”, and operate
the TV set for more than 15 minutes.
2. Set the picture menu to “DYNAMIC NORMAL” and the AI to
off.
3. Connect an oscilloscope to TPL7 with DC mode.
4. Set the TV set to Market Mode : white balance adjustment
4. Set the TV set to Market Mode : white balance adjustment
(CHK 3).
5. Screen VR : Min.
6. Set the data level of SUB BRIGHT, R, G, B-CUTOFF and
6. Set the data level of SUB BRIGHT, R, G, B-CUTOFF and
R, G, B-DRIVE to the table values.
Display
Date Level
R-CUT OFF
63
G-CUT OFF
128
B-CUT OFF
63
R-DRIVE
128
B-DRIVE
128
SUB BRIGHT
63
Adjustment
1. Select G-CUTOFF adjustment mode and collapse vertical
1. Select G-CUTOFF adjustment mode and collapse vertical
scan.
2. Adjust G-CUTOFF control to become the DC=0 V to video
level at 180 V as shown in Fig. 1.
Fig. 1
3. Slowly turn the screen control clockwise until a green colour
horizontal line appears on the picture tube. This is the
setting point for the screen control.
Note:
Do not adjust the G-CUTOFF setting in the following
procedure.
setting point for the screen control.
Note:
Do not adjust the G-CUTOFF setting in the following
procedure.
4. Adjust the remaining R and B-CUTOFF controls so as to
get a white horizontal line on the screen.
5. Return to full field SCAN by pushing the position 5 key on
the remote control.
6. Adjust the R-Drive and B-Drive controls as to obtain a
uniform white on the white bar of the greyscale pattern.
7. Confirm correct B/W rendition and greyscale tracking or
repeat CUTOFF and drive control setup.
Note:
Note:
Write down the original value for each address adjustment
before adjusting anything.
before adjusting anything.
8. Wedge A shown in Fig. 2 should be fixed within a range of
45° to the left of the vertical line as shown.
9. After inserting wedge A, insert wedges B, C and D.
The wedges should be set 90° apart from each other.
10. Be certain that the four wedges are firmly fixed and the
deflection yoke is tightly clamped in place otherwise the
deflection yoke may shift its position and cause a loss of
convergence and purity.
deflection yoke may shift its position and cause a loss of
convergence and purity.
5.10. WHITE BALANCE (MARKET MODE CHK 3)
11
TX-25P80T
TX-25P80T
12
6 CONDUCTOR VIEWS
6.1. T-Board (TNP4G115AH) and L-Board (TNP4G107AW)
Click on the first or last page to see other TX-25P80T service manuals if exist.