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SERVICE ADJUSTMENT
VCO AdjustmentWhite Balance Adjustment
1. Connect a digital voltmeter between pin (44) of IC2011. Receive a good local channel.
and ground.2. Enter the service mode and select the service
2. Receive a good local channel.adjustment "S03" and set to "00" (minimum color).
3. Enter the service mode and select the service"S03" does not have to be adjusted, if you selected a
adjustment "S10".B/W picture or monoscope pattern.
4. Adjust the data so that digital voltmeter reads 2.2V.3. Alternately adjust the service adjustment data of "S14"
5. Adjustment is completed, remove the voltmeter, returnand "S15" until a good grey scale with normal whites
to "normal" mode.is obtained.
4. Select the service adjustment "S03" and adjust data
RF AGC Adjustmentto obtain normal color level.
1. Receive a good local channel.Sub-Picture Adjustment
2. Enter the service mode and select the service
adjustment "S08".1. Receive a good local channel.
3. Set the data value to point where no noise or beat2. Make sure the customer picture control is set to
appears.maximum.
4. Select another channel to confirm that no noise or3. Enter the service mode and select the service
beat appears.adjustment "S01".
Note 1 : You will have to come out of the service4. Adjust the data value to achieve normal contrast
mode to select another channel.range.
Note 2 : Setting the data to "00" will produce a black
raster.Sub-Tint Adjustment
Screen Adjustment1. Receive a good local channel.
2. Set customer tint control to center of it's range.
1. Connect a digital voltmeter between TP852 and3. Enter the service mode and select the service
TP853 on the CRT socket PWB.adjustment "S02".
Note : These test points may not be provided.4. Adjust "S02" data value to obtain normal flesh tones.
Then connect the voltmeter to both ends of
R852 located near Q852 on the foil side.+115V DC REGULATOR Adjustment
2. Receive a good local channel.
3. Enter the service mode and select the serviceThe +115V DC Adj. control (R721) is adjusted at the
adjustment "S03" and set the data value to "00" tofactory. However, should readjustment be required,
set the color level to minimum. (Record original dataproceed as follows:
code under adjustment "S03" before changing) You1. Actuate the receiver with 220V AC input voltage.
may skip this step, if you selected a B/W picture or2. Select a local channel.
monoscope pattern.3. Connect positive lead of Digital Voltmeter to R603
4. Select the service adjustment "S19" and adjust theTP751 (positive side) on PWB-A; negative lead to
data value to "01", this turn off the luminance signalchassis ground.
4. Adjust R721 to obtain a +115V DC reading.
(Y-mute).CAUTION: The reading should be within +115V -1VDC
5. Select the service adjustment "S04" and adjust datato ensure normal function and circuitry
value to obtain 0.17 volts on the oscilloscope screen.reliability.
6. Adjust the master screen control until the raster
darkens to the point where raster is barely seen.
7. Adjust the service adjustments "S11" red, "S12" green
and "S13" blue to obtain a good grey scale with
normal whites at low brightness level.
8. Select the service adjustment "S19" and reset data
to "00". Select the service adjustment "S03" and reset
data to obtain normal color level.
9. Remove digital voltmeter, and reset the master screen
control to obtain normal brightness range.
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ACEC
