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72FF-57E
81FF-57E
All the adjustments required for this chassis will be done in Service Mode, except G2 and Focus.
• • • • • G2 ADJUSTMENT
1. Receive cross hatch pattern signal.
2. Set Picture Adjustement to Factory Settings (contrast to 70%,
brithness to 40%)
3. Connect the oscilloscope to the red cathode and adjsust G2 to read
145V on the sensor pulse as in the drawing:
NOTE:
Oscilloscope should be adjusted for vertical TV field trigger and synchronized
with wideo signal.
• • • • • IF PLL ADJUSTMENT (AFT) B/G, L, I
1. Disconnect antenna signal.
2. Connect the output of SSG (Standard Signal Generator, colour bars) to the output terminal
• • • • •
SSG output:
• • • • •
SSG output level:
• • • • •
Probe:
3. Connect the digital voltmeter to TP202
4. Adjust the AFT coil (L 205) to obtain 4.5V
• • • • • IF PLL ADJUSTMENT (AFT) L'
1. Disconnect antenna signal.
2. Connect the output of SSG (Standard Signal Generator, monoscope) to the output terminal
• • • • •
SSG output:
• • • • •
SSG output level:
• • • • •
Probe:
3. Connect the digital voltmeter to TP202
4. Adjust the AFT R 226 to obtain 4.5V
• • • • • RF AGC ADJUSTMENT
1. Receive «COLOUR BAR» signal (UHF)
• • • • •
Signal strength:
2. Connect DC Voltmeter to Test Point TP201 (RF AGC).
3. Set AGC control (R224) to maximum position (memory).
4. Adjust R224 to obtain voltage of 0.1 V below maximum voltage (step 3).
• • • • • SERVICE MODE FUNCTION
This mode function is provided to assist with the settings of those adjustments that may vary from one
Picture Tube to another, or between models.
In order to use the Service Mode:
1. Connect Test Pattern signal to antenna terminal.
Set to full mode screen by wide button.
2. Press main switch to «OFF».
3. Press volume-down and channel-up buttons and
main switch to «ON» simultaneously.
4. Service mode is now entered.
SERVICE ADJUSTMENTS
38.9 MHz (CW)
µ
approx. 90 dB
Direct.
on voltmeter.
DC
±
33.9 MHz (CW)
µ
approx. 90 dB
V
Direct.
on voltmeter.
DC
µ
60 dB
V
4
CH1 gnd
±
5 KHz
V
5 KHz
CH1
20 V
A 2 ms
TVF1
5
B 50 ms
95.40 V
145V
CH
1
2
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