Akira CT-21LS9MTS Schematic
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Model: CT-21LS9MTS
Chassis: 3Y03
Model No: CT-21LS9MTS
Version 1.0
3
CONTENT
SERVICE ADJUSTMENT ...................................................................................................................... 4
COMPLETE MACHINE GENERAL ADJUSTMENT........................................................................... 6
FACTORY MENU DISCRIPTION......................................................................................................... 8
CONTROL LOCATION........................................................................................................................ 11
INPUT & OUTPUT TERMINALS........................................................................................................ 12
MECHANICA DISASSEMBLING....................................................................................................... 13
CABINET PARTS LIST........................................................................................................................ 15
CIRCUIT DIAGRAM............................................................................................................................ 16
Model No: CT-21LS9MTS
Version 1.0
4
SERVICE ADJUSTMENTS
Please notice the following before alignment and equipment
1. Don’t short any two soldering points, which should not be shorted and don’t touch any
components, which should not be touched.
2. Please pull out plug before equipment.
3. For safety reasons, all components equipped or replaced should be identical with BOM.
4. Must be warm up for 30 minutes or more and degauss CRT thoroughly with demagnetizer before
alignment.
The data of EEPROM must be stored before the adjustment for main chassis and EEPROM must be
corrected by the correct file 3Y03 ROM CORRECT.hex to avoid signal of CH6 weaken. R.bias,
G.bias, B.bias, R.drv, G.drv, B.drv should be set to proper values. Sub_bright is set to 63 usually.
Tools and equipments for adjustment
1. Small (-) screwdriver
2. Screwdriver without inductance
3. Pattern generator
4. DC Regulated power supply
5. Digital voltmeter
6. Sweep signal generator
7. 20MHz 2-Channel oscilloscope
Signal condition
ITEMS LOGO PICTURE
CARRIER
1 CH14 471.25MHz COLOR BAR NTSC/M MONO 1KHz
2 CH3 61.25MHz GRAY SCALE NTSC/M BTSC
3 CH8 181.25 MHz MONOSCOPE NTSC/M MONO MUSIC
4 CH12 205.25 MHz CROSS HATCH NTSC/M MONO 1KHz
Adjust for main chassis
PIF Adjustment (45.75MHz)
1. Tuner AGC connects to GND. Pattern generator outputs 45.75MHz IF. Signal (70db V) and
connects to SAW filter output terminal through a capacitor.
2. Connect digital voltmeter across C227. DC regulated power supply positive terminal output +14V
to C617.
3. Adjust L203 coil to obtain 3.6V Digital voltage meter reading.
Note: To cancel this adjustment, L203 can be adjusted before inserted to the chassis with a special
equipment.
Model No: CT-21LS9MTS
Version 1.0
PATTERN SYSTEM SOUND
MODE
0.3K, 3KHz
5
B+ adjustment
1. Disconnect horizontal load. Connect a bulb (100W) AC 250V across C321.
2. Add 220V AC 50HZ to CN601 and switch on power switch.
3. Test the voltage with digital voltage meter between C321 two terminals.
4. Adjust VR601 to obtain +110V – 0.5V.
AGC alignment
1. Receive 60dB RF signal. Connect digital voltmeter positive terminal to tuner AGC terminal and
negative terminal to GND.
2. Press MENU key, then press Q.VIEW key, MUTE key in turn on telecontroller. TV SET will go to
factory mode. Press TIMER key to go to the next factory menu. Go to MENU5 status by this
means. Press MENU key to exit factory mode.
3. Select RF.AGC by pressing CH+ and CH- keys. Adjust VOL+ and VOL- keys to obtain 4V digital
voltage meter reading.
Model No: CT-21LS9MTS
Version 1.0
6
COMPLETE MACHINE GENERAL ADJUSTMENT
Go to factory mode according to 4-2-2 before warm up line Focus adjustment
1. Receive monoscope pattern.
2. Set TV to work in dynamic status.
3. Adjust the focus knob of FBT to get the clearest picture.
Screen voltage adjustment
1. Check the R.bias, G.bias, B.bias, R.drv, G.drv, B.drv and sub_bright. Go to factory mode MENU2
status according to 4-2-2. Usually G.bias should be same as the value of auto white balance
equipment. And SUB_BRIGHT is 63.
2. Set Cross_BW 3. Then the picture will be a white +. Cross_BW is in factory menu 3.
3. In menu 5, select SUBB.ADJ and set it to 1. Adjust the screen knob of FBT to get a faintness +.
4. Restore the SUBB.ADJ to 0 and CROSS.BW to 0.
White balance adjustment (Applied in factory)
1. Set TV AV status in custom mode (or other mode need for the adjustment). Receive black white
pattern.
2. Insert six-row-wire into CN002. Press adjustment keys and then go to automatic white balance
adjustment.
3. PIN DISCRIPTION OF CN002:
1●●SDA●●2●●SCL●●3●●GND●●4●●GND●●5●●SCL●●6●●SDA
4. After adjust well, pull out six-row-wire.
White balance adjustment (Applied when servicing)
1. Set TV AV status and receiv GREY SCAL.
2. The one sampling tube of CRT color analyzer (CA-100) covers on GREY signal and the another
covers on white signal.
3. Go to factory mode MENU2. Obtain GREY signal X=281 and y=311 by adjusting R-CUT and Bcut. Obtain white signal X=281 and y=311 adjusting R-DRV and B-DRV. Obtain both X=281 and
Y=311 by adjusting the two status repeatedly.
Sub_Bright adjustment
Receive the grey scale. Get into the menu5 of factory mode. Set SUBB.ADJ to 1. Then adjust the
SUB.BRI option to get a scale to be seen a little brightness (only two rows can be seen).
Vertical size and Pin Cushion adjustment
1. Receive monoscope pattern. Set TV standard status. Adjust V.size to obtain pictures vertical
redisplay ratio mode than 90% in factory mode MENU1.
2. Receive cross hatch pattern. Set TV standard status. Adjust V.LINE and V.SC to obtain picture
vertical pin cushion a good status in factory mode MENU1.
3. Receive cross hatch pattern. Set TV standard status. In factory mode MENU1 adjust V.POS to
obtain pictures vertical center at the center of CRT screen.
Horizontal Center adjustment and horizontal position of OSD adjustment
1. Receive monoscope PATTERN. Set TV standard status. Adjust H.PHASE in menu 1. to obtain
horizontal center at the center of CRT screen.
2. Adjust OSD.HPOS to get right display position.
Model No: CT-21LS9MTS
Version 1.0
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