Noblex
Model No. 20TC662 – How to enter the service mode, full schematic, service
adjustments PAL (M/M, N/N), NTSC (M/M) (Argentina) Colour Television
Service Adjustments
This
set has an On-screen Service Menu system included in the CPU thar allows remote
operation for most of the service adjustments.
Enter the Service Menu
While pressing the MENU button on the television, press the Number Key 2 on the remote control unit. The Service Menu now appear.
While pressing the MENU button on the television, press the Number Key 2 on the remote control unit. The Service Menu now appear.
Service Adjustments:
Press the CHANNEL UP or CHANNEL DOWN button on the remote control handset to select the desired service menu item you want to adjust.
Use the VOLUME + or - to adjust the data. The + or - button will increase or decrease the data sequentially.
Exit from the Service MenuPress the CHANNEL UP or CHANNEL DOWN button on the remote control handset to select the desired service menu item you want to adjust.
Use the VOLUME + or - to adjust the data. The + or - button will increase or decrease the data sequentially.
Press the MENU button to turn off the Service Menu display.
The data which is set in the service mode is stored into the memory IC automatically.
The initial values which have been stored in the CPU ROM, and items for the service adjustments.
The data which is set in the service mode is stored into the memory IC automatically.
The initial values which have been stored in the CPU ROM, and items for the service adjustments.
Do
not attempt to adjust service adjustments not listed on below otherwise it may
cause loss of performance and for correct operation.
Click on the pictures to magnify
[RFAGC] AGC
Do
not attempt this adjustment with weak signal.
(1) Tune the receiver to most clearest (or strongest) VHF station in your area. Set the brightness and contrast controls to maximum. Set the colour control to minimum.
(2) Select Item No. 01 [RFAGC] in the service mode.
(3) Change value until the snow noise just disappears.
(4) Exit from the service mode.
(1) Tune the receiver to most clearest (or strongest) VHF station in your area. Set the brightness and contrast controls to maximum. Set the colour control to minimum.
(2) Select Item No. 01 [RFAGC] in the service mode.
(3) Change value until the snow noise just disappears.
(4) Exit from the service mode.
[H-PHA] HORIZONTAL CENTRE
(1) Receive a monochrome circular pattern.
(2) Set the brightness and contrast to normal.
(3) Select Item No. 02 [H-PHA] in the service mode.
(4) Change value to be optimum horizontal centre position.
(5) Exit from the service mode.
(2) Set the brightness and contrast to normal.
(3) Select Item No. 02 [H-PHA] in the service mode.
(4) Change value to be optimum horizontal centre position.
(5) Exit from the service mode.
[V-POS] VERTICAL CENTRE
(1)
Receive a monochrome circular pattern.
(2) Set the brightness and contrast to maximum.
(3) Select Item No. 03 [V-POS] in the service mode.
(4) Change value to be optimum vertical centre position.
(5) Exit from the service mode.
(2) Set the brightness and contrast to maximum.
(3) Select Item No. 03 [V-POS] in the service mode.
(4) Change value to be optimum vertical centre position.
(5) Exit from the service mode.
[V-SIZ] VERTICAL SIZE
(1)
Receive a monochrome circular pattern.
(2) Set the brightness and contrast to maximum.
(3) Select Item No. 04 [V-SIZ] in the service mode.
(4) Change value to be optimum vertical size.
(5) Exit from the service mode.
(2) Set the brightness and contrast to maximum.
(3) Select Item No. 04 [V-SIZ] in the service mode.
(4) Change value to be optimum vertical size.
(5) Exit from the service mode.
[OSDHP] OSD POSITION
(1)
Receive a monochrome circular pattern.
(2) Set the brightness and contrast to normal.
(3) Select Item No. 12 [OSDHP] in the service mode.
(4) Change value to be proper OSD position.
(5) Exit from the service mode.
(2) Set the brightness and contrast to normal.
(3) Select Item No. 12 [OSDHP] in the service mode.
(4) Change value to be proper OSD position.
(5) Exit from the service mode.
[AFCRF] AFC GAIN
(1)
Switch on the TV.
(2) Select Item No. 65 [AFCRF] in service mode.
(3) Change data value to “01”.
(4) Exit from the service mode.
(2) Select Item No. 65 [AFCRF] in service mode.
(3) Change data value to “01”.
(4) Exit from the service mode.
[CCD] CAPTION H-POSITION ADJ
(1)
Tune receiver to a caption channel.
(2) Check that CAPTION position is in the horizontal center of the screen. If CAPTION center is too right or left, perform steps 3-6.
(3) Select Item No. 85 [CCD] in the service mode.
(4) Adjust data with + or - key for proper horizontal center.
(5) Exit from the service mode
(2) Check that CAPTION position is in the horizontal center of the screen. If CAPTION center is too right or left, perform steps 3-6.
(3) Select Item No. 85 [CCD] in the service mode.
(4) Adjust data with + or - key for proper horizontal center.
(5) Exit from the service mode
GREY SCALE
(1) Receive a monochrome circular pattern.
(2) Set the brightness and colour to normal, contrast to maximum.
(3) Enter to the service mode.
(4) Set each value of Item-16 RBIAS, 17 GBIAS, 18 BBIAS mode to 00. Set each value of Item-19 RDRIV, 21 BDRIV mode to 63, 20 GDRIV to 07.
(5) Select Item-22 mode to be one horizontal scanning line and turn the screen volume on the FBT to obtain just visible one colored line.
(6) Press the 1 (Red Bias +), 4 (Red Bias -), 2 (Green Bias +), 5 (Green Bias -), 3 (Blue Bias +) or 6 (Blue Bias -) button to adjust the brightness of each colour until a dim white line produced. Please see the control button allocations in this mode.
(7) Select Item-23 DRV mode to enter the white balance adjusting mode.
(8) Press the 7 (Red Drive +), RECALL (Red Drive -), 8 (Blue Drive +) or 0 (Blue Drive -) button alternately to produce normal black and white picture.
(9) Exit from the service mode.
(10) Check for proper grey scale tracking at all brightness levels.
NOTE: If the grey scale adjustment is made after picture tube replacement, check the high voltage.
(2) Set the brightness and colour to normal, contrast to maximum.
(3) Enter to the service mode.
(4) Set each value of Item-16 RBIAS, 17 GBIAS, 18 BBIAS mode to 00. Set each value of Item-19 RDRIV, 21 BDRIV mode to 63, 20 GDRIV to 07.
(5) Select Item-22 mode to be one horizontal scanning line and turn the screen volume on the FBT to obtain just visible one colored line.
(6) Press the 1 (Red Bias +), 4 (Red Bias -), 2 (Green Bias +), 5 (Green Bias -), 3 (Blue Bias +) or 6 (Blue Bias -) button to adjust the brightness of each colour until a dim white line produced. Please see the control button allocations in this mode.
(7) Select Item-23 DRV mode to enter the white balance adjusting mode.
(8) Press the 7 (Red Drive +), RECALL (Red Drive -), 8 (Blue Drive +) or 0 (Blue Drive -) button alternately to produce normal black and white picture.
(9) Exit from the service mode.
(10) Check for proper grey scale tracking at all brightness levels.
NOTE: If the grey scale adjustment is made after picture tube replacement, check the high voltage.
FINE TUNING
This
adjustment is used to do a fine tuning of the channels with poor reception
after they have been stored by the automatic tuning.
This function is available for one channel only and the fine-tuned channel is memorized into IC802 (EEPROM).
This function is available for one channel only and the fine-tuned channel is memorized into IC802 (EEPROM).
Enter
Service Menu
While pressing the MENU button on the television, press the “4” or MENU button on the remote control unit. The Service Menu now appear.
While pressing the MENU button on the television, press the “4” or MENU button on the remote control unit. The Service Menu now appear.
Press
and hold the VOLUME + or VOLUME – button on the remote control handset or TV
set to make fine tuning adjustment. Press and hold the VOLUME + button for
higher frequency tuning, and press and hold the VOLUME - for lower frequency
tuning.
Fine
tuning data value will be automatically stored in memory.
To
return to normal TV mode, press the MENU button on the TV set or remote control
handset. (Or will automatically return to normal TV mode after 5 seconds.)
FOCUS ADJUSTMENT
(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.
(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.
+B POWER SUPPLY 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 anactive channel and synchronized picture.
4. Adjust +B voltage to 130± 1.0 volt DC by using VR651.
2. Set the brightness to normal and contrast to maximum.
3. Tune the receiver to anactive channel and synchronized picture.
4. Adjust +B voltage to 130± 1.0 volt DC by using VR651.
HIGH VOLTAGE CHECK
Note:
+B (+130V) Voltage Check and Grayscale Adjustment must be completed before
attempting High Voltage Check.
(1) Connect high voltage voltmeter negative lead to ground, and connect + 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 14”=21KV ± 1KV, 20”/21”=25KV ± 1KV, 29”=26.5KV ± 1KV and less than 14”=25KV, 20”/21”=27.5KV, 29”=29.5KV at 0 beam current (Brightness and contrast minimum setting).
Note: If the picture tube is replaced, check the high voltage. The horiz. width adjustment affects the high voltage. Therefore, re-check the high voltage.
(1) Connect high voltage voltmeter negative lead to ground, and connect + 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 14”=21KV ± 1KV, 20”/21”=25KV ± 1KV, 29”=26.5KV ± 1KV and less than 14”=25KV, 20”/21”=27.5KV, 29”=29.5KV at 0 beam current (Brightness and contrast minimum setting).
Note: If the picture tube is replaced, check the high voltage. The horiz. width adjustment affects the high voltage. Therefore, re-check the high voltage.
Full
Schematic [Circuit diagram]
Protection Circuit
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 standby mode.
When
an abnormality occurs during TV reception, it causes pin 27 of the CPU to go
continually Low voltage 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 restoring 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 trouble
was temporary. If there is permanent trouble such as a damaged circuit, power
cannot be restored and the circuit will have to be repaired.
Purity and Convergence Adjustment
The
Convergence and Purity adjustments have been made at the factory. Readjustment
should be made only after picture tube or deflection yoke replacement,
following the steps below
PURITY ADJUSTMENT
1. Demagnetize the picture tube and receiver using an external degaussing coil. When replacing picture tube or deflection yoke, mount deflection yoke and purity-convergence magnets assembly properly,
2. Turn Red and Blue guns off and provide only Green raster. Rotate Screen control to fully counterclockwise. Rotate Red and Blue Bias controls fully counterclockwise. Slowly rotate Green Bias control clockwise to produce Green raster.
3. Loosen the screw holding the Deflection Yoke and remove the 3 Rubber Wedges, and slide the Deflection Yoke fully forward.
4. Rotate and spread the Tabs of the two Purity Magnets to centre the vertical green belt in the picture screen. The Purity Magnets are also adjusted to obtain vertical centering of the raster.
5. Slowly slide the Deflection Yoke backward until a uniform green screen is obtained.
6. Check the purity of the red and blue screens for uniformity, turn off other colors to check this (use bias controls). Readjust the yoke position if necessary until all screens are pure.
7. Adjust each Bias control and screen control to obtain white raster. Refer to Gray Scale Adjustment. If part of the picture screen is coloured, adjust the Deflection Yoke position forward or backward slightly.
1. Demagnetize the picture tube and receiver using an external degaussing coil. When replacing picture tube or deflection yoke, mount deflection yoke and purity-convergence magnets assembly properly,
2. Turn Red and Blue guns off and provide only Green raster. Rotate Screen control to fully counterclockwise. Rotate Red and Blue Bias controls fully counterclockwise. Slowly rotate Green Bias control clockwise to produce Green raster.
3. Loosen the screw holding the Deflection Yoke and remove the 3 Rubber Wedges, and slide the Deflection Yoke fully forward.
4. Rotate and spread the Tabs of the two Purity Magnets to centre the vertical green belt in the picture screen. The Purity Magnets are also adjusted to obtain vertical centering of the raster.
5. Slowly slide the Deflection Yoke backward until a uniform green screen is obtained.
6. Check the purity of the red and blue screens for uniformity, turn off other colors to check this (use bias controls). Readjust the yoke position if necessary until all screens are pure.
7. Adjust each Bias control and screen control to obtain white raster. Refer to Gray Scale Adjustment. If part of the picture screen is coloured, adjust the Deflection Yoke position forward or backward slightly.
8.
Tighten the mounting screw of the Deflection Yoke. Adjust Convergence next.
CENTRE CONVERGENCE ADJUSTMENT
1. Use a dot crosshatch pattern signal.
2. Turn Red and Blue guns on and turn off Green gun. Adjust the angle between the Tabs of the Four Pole Magnet 1 and 2, and superimpose the Red and Blue vertical lines in the centre area of the picture screen.
3. Keeping the mutual angle of the Tabs of the Four Pole Magnet turn them together to superimpose the Blue and Red horizontal lines in the centre area of the picture screen.
1. Use a dot crosshatch pattern signal.
2. Turn Red and Blue guns on and turn off Green gun. Adjust the angle between the Tabs of the Four Pole Magnet 1 and 2, and superimpose the Red and Blue vertical lines in the centre area of the picture screen.
3. Keeping the mutual angle of the Tabs of the Four Pole Magnet turn them together to superimpose the Blue and Red horizontal lines in the centre area of the picture screen.
4.
Turn Green gun on and adjust Six Pole Magnet 3 and 4 that the Green line
superimposed on the Red/Blue lines. This
is the same procedure used in steps 2 and 3.
OUTER AREA CONVERGENCE ADJUSTMENT
Slightly loosen the screw holding the Deflection Yoke. Adjust the Deflection Yoke to converge the detail in the outer area (left side and right side) of the picture screen by orbital movement of the front of the Yoke, then secure the Deflection Yoke in appropriate position by putting the wedges as illustrated. Tighten screw holding the Deflection Yoke.
OUTER AREA CONVERGENCE ADJUSTMENT
Slightly loosen the screw holding the Deflection Yoke. Adjust the Deflection Yoke to converge the detail in the outer area (left side and right side) of the picture screen by orbital movement of the front of the Yoke, then secure the Deflection Yoke in appropriate position by putting the wedges as illustrated. Tighten screw holding the Deflection Yoke.
Universal Remote Control Codes, Setup procedure, Circuit diagrams and more ....
