Fisher PC-R20R2 Service Manual page 11

Service Adjustments
B+ adjustment
a. Disconnect horizontal load. Connect a bulb (100 W) AC 250V across C321.
b. Add 220V AC 50HZ to CN601 and switch on power switch.
c. Test the voltage with digital voltage meter between C321 two terminals.
d. Adjust VR601 to obtain +110V¡À0.5V.
AGC alignment
a. Receive 60dB RF signal. Connect Digital voltmeter positive terminal to tuner AGC terminal and negative terminal
to GND.
b. 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.
c. Select RF.AGC by pressing "CH+" and "CH-"keys. Adjust "VOL+" and "VOL-" keys to obtain 4V Digital voltage
meter reading.
COMPLETE MACHINE GENERAL ADJUSTMENT
Go to factory mode according to 4-2-2 before warm up line
Focus Adjustment
a. Receive monoscope pattern.
b. Set TV to work in dynamic status.
c. Adjust the focus knob of FBT to get the clearest picture.
Screen Voltage Adjustment
a. 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.
b. Set Cross_BW '3". Then the picture will be a white "+". Cross_BW is in factory menu 3.
c. In menu 5, select SUBB.ADJ and set it to "1". Adjust the screen knob of FBT to get a faintness "+".
d.
Restore the SUBB.ADJ to "0" and CROSS.BW to "0".
White Balance Adjustment (Applied in factory)
a. Set TV AV status in custom mode(Or other mode need for the adjustment) . Receive black white pattern.
b. Insert six-row-wire into CN002.Press adjustment keys, and then go to automatic white balance adjustment.
PIN DISCRIPTIONN OF CN002:
c.
1£ºSDA£¬ 2£ºSCL£¬ 3£ºGND£¬ 4£ºGND£¬ 5£ºSCL£¬ 6£ºSDA¡£
d. After adjusting well, pull out six-row-wire.
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