Wednesday, February 18, 2015

NOBLEX 21TC647 - 29TC649 CRT TV SERVICE MODE AND ADJUSTMENTS

NOBLEX 21TC647 - 29TC649

 CRT TV 


SERVICE MODE AND ADJUSTMENTS 

Entering to Service Mode
1. Press and hold the MENU button on the TV set and press the 2 button on the remote control handset. Following setting items appears on the screen.
2. Select item by pressing the CHANNEL DOWN (Item No. UP) or CHANNEL UP (Item No. DOWN) button on the remote control handset.
3. Adjust data value by pressing the VOLUME + or VOLUME - button on the remote control handset.
To return to normal TV mode, press the MENU button on the TV set or remote control handset.
[H-P] HORIZONTAL CENTRE
(1) Receive the monochrome circular pattern.
(2) Set the brightness and contrast to normal.
(3) Select [H-P] in the service mode.
(4) Change value to be optimum horizontal centre position.
(5) Exit from the service mode.
[V-P] VERTICAL CENTRE
(1) Receive the monochrome circular pattern.
(2) Set the brightness and contrast to maximum.
(3) Select [V-P] in the service mode.
(4) Change value to be optimum vertical centre position.
(5) Exit from the service mode.
[V-S] VERTICAL SIZE
(1) Receive the monochrome circular pattern.
(2) Set the brightness and contrast to maximum.
(3) Select [V-S] in the service mode.
(4) Change value to be optimum vertical size.
(5) Exit from the service mode.
[OSD] OSD POSITION
(1) Receive the monochrome circular pattern.
(2) Set the brightness and contrast to normal.
(3) Select [OSD] in the service mode.
(4) Change value to be proper OSD position.
(5) Exit from the service mode.
[AGC] AGC
NOTE: 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 [AGC] in the service mode.
(3) Change value until the snow noise just disappears.
(4) Exit from the service mode.
[VCO] AFT
(1) Connect DC meter to TP-D and the ground.
(2) Tune the receiver to the clearest station.
(3) Disconnect RF input. (Disconnect antenna plug from the antenna socket.)
(4) Select same channel. (If you have selected channel 03 in step 2, press “0” button next “3” button on the remote control to select channel 03.)
(5) Connect antenna plug to the antenna socket.
(6) Select [VCO] in the service mode.
(7) Change value until the voltage (on TP-D) to be 4.5±0.2V at OK point.
GREY SCALE
(1) Receive the 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-18 RBI, 19 GBI, 20 BBI mode to 00. Set each value of Item-21 RD, 22 BD mode to 64.
(5) Select Item-24 mode to be one horizontal scanning line and turn the screen volume on the FBT to obtain just visible one coloured 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 +), CHANNEL 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.
Entering to MTS Adjustment Service Mode
1. Press and hold the MENU button on the TV set and press the 3 button on the remote control handset. Following setting items appears on the screen.
2. Select item by pressing the CHANNEL DOWN (Item No. UP) or CHANNEL UP (Item No. DOWN) button on the remote control handset.
3. Adjust data value by pressing the VOLUME + or VOLUME - button on the remote control handset.
To return to normal TV mode, press the MENU button on the TV set or remote control handset.
SOUND LEVEL ADJUSTMENT
1. Connect a signal generator to TP-301(- side of C3407) on the Main Board and the ground. Signal output=300Hz, 150mVrms.
2. Connect a DC Volt-Meter to TP-317( + side of C3437) and the ground.
3. Ground TP-20(pin-45 of IC201) with the jumper lead.
4. Switch the TV set on. Press and hold the MENU button on the TV set, and press “3” button on the remote control transmitter to enter to the service mode.
5. Adjust voltage to become DC 500mVrms±10mVrms by pressing the VOLUME(+/-) button on the remote control or TV set.
6. To exit from the service mode, press the MENU button.
STEREO VCO ADJUSTMENT
1. Connect a frequency counter to TP-317( + side of C3437) and the ground.
2. Ground TP-20(pin-45 of IC201) with the jumper lead.
3. Switch the TV set on. Press and hold the MENU button on the TV set, and press “3” button on the remote control transmitter to enter the service mode.
4. Select “STEREO VCO” by pressing the CHANNEL UP/DOWN button on the remote control or TV set.
5. Adjust the frequency to become 15.625KHz ± 0.1KHz by pressing the VOLUME (+/-) button on the remote control or TV set.
6. To exit from the service mode, press the MENU button.
MTS FILTER ADJUSTMENT
1. Connect a signal generator to TP-301(- side of C3407) and the ground. Signal output=15.734KHz, 100mVrms.
2. Connect a DC Volt-Meter to TP-317( + side of C3437) and the ground.
3. Ground TP-20(pin-45 of IC201) with the jumper lead.
4. Switch the TV set on. Press and hold the MENU button on the TV set, and press “3” button on the remote control transmitter to enter the service mode.
5. Select “FILTER” by pressing the CHANNEL UP/DOWN button on the remote control or TV set.
6. Adjust voltage to become minimum reading by pressing the VOLUME(+ -) button on the remote control or TV set.
7. To exit from the service mode, press the MENU button.
STEREO SEPARATION ADJUSTMENT
1. Connect an oscilloscope:
Probe-A to TP-317(+ side of C3437) and the ground.
Probe-B to TP-318 (+ side of C3438) and the ground.
2. Switch the TV set on, and receive the multi sound program.
3. Press and hold the MENU button on the TV set, and press “3” button on the remote control transmitter to enter to the service mode.
4. Select “LOW SEPARATION” by pressing the CHANNEL UP/DOWN button on the remote control or TV set.
5. Adjust level of 300Hz at TP-317 (+ side of C3437) to become minimum level by pressing the VOLUME(+/ -) button on the remote control or TV set.
6. Select “HI SEPARATION” by pressing the CHANNEL UP/DOWN button on the remote control or TV set.
7. Adjust level of 4KHz at TP-318 (+ side of C3438) to become minimum level by pressing the VOLUME (+/-) button on the remote control or TV set.
8. To exit from the service mode, press the MENU button.
SAP VCO ADJUSTMENT
1. Connect a frequency counter to TP-317(+ side of C3437) and the ground.
2. Ground TP-20 (pin-45 of IC201) with the jumper lead.
3. Ground TP-316(+ side of C3411) with the jumper lead through 1M Ω resistor.
4. Switch the TV set on.
5. Press and hold the MENU button on the TV set, and press “3” button on the remote control transmitter to enter to the service mode.
6. Select “SAP VCO” by pressing the CHANNEL UP/DOWN button on the remote control or TV set.
7. Adjust frequency of the counter to become 78.125KHz ±0.5KHz by pressing the VOLUME (+/-) button on the remote control or TV set.
8. To exit from the service mode, press the MENU button.
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).
1. Press and hold the MENU button on the TV set and press the 4 or MENU button on the remote control handset to enter to the service mode.
2. 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 or lower frequency tuning.

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.
HORIZ. WIDTH AND HIGH VOLTAGE CHECK 
(1) Receive the monochrome circular pattern.
(2) Set the brightness and contrast to maximum.
(3) If the picture is too wide, or narrow, cut or short the “AJ1 ” on the main unit. When AJ1 is shorted, the horizontal width increase. When AJ1 is cut, the horizontal width decrease.
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(4) Connect a high voltage probe to anode lead of the picture tube.
(5) 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 (Brightnees and contrast minimum setting).