Service manual

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SIF Adjustment
Note: Be sure to perform this adjustment whenever the SIF coil (L201) is replaced.
Simplified adjustment procedure
Input signal: Normal off-the-air broadcast
Measuring equipment: Oscilloscope
Adjustment point: L201
Test point: IC301 pin-54
Adjustment method: Adjust L201 so that the center value of the audio signal waveform at IC301 pin-54 becomes 4.5±0.2 Vdc.
RF AGC Adjustment
Input signal: RF input
Input level: 60 dBµV, P/S 7 dB
Channel: 11 CH (fp = 199.25 MHz)
Video: Color bars (full field)
Audio: 400 Hz
Modulation degree: Video 87.5%, audio 100% (±25 kHz deviation)
Measuring equipment: Pattern generator, oscilloscope
Test point: TP101, RF AGC
Adjustment point: Adjustment menu PAGE 1-6
Adjustment method: Connect an oscilloscope to TP 101. Adjust the voltage at the test point for 4.0±0.5 Vp-p using the jig remote
controller VOLUME UP/DOWN keys.
SCREEN VOLTAGE Adjustment
Note: Be sure to perform the WHITE BALANCE Adjustment whenever the SCREEN VOLTAGE Adjustment is performed.
Input signal: No input signal
Measuring equipment: Oscilloscope
Test point: SO901 R, G, B
Adjustment point: Adjustment menu PAGE 2-1, 2-2, 2-3 SCREEN VR (FBT: T601)
Adjustment method:
1. Connect an oscilloscope to SO901 R (R cathode). Adjust the adjustment menu PAGE 2-1 "1. R CUTOFF" so that the voltage
as shown in the illustration becomes 175±2 V.
2. Perform the SCREEN VOLTAGE adjustment for the G and B channels in the same manner as step 1 for the R channel.
3. Press the numeric key "0" of the jig adjustment remote controller on the adjustment menu screen so that the horizontal single
line display on the screen.
4. Adjust the SCREEN VR to the point where the horizontal single line display just starts illuminating.
5. Press the numeric key "0" of the jig remote controller to return to the menu screen.
FOCUS Adjustment
Input signal: Dot-pattern signal
Measuring equipment: Pattern generator
Adjustment point: FOCUS VR (FBT:T601)
Adjustment method: Adjust the FOCUS VR (FBT:T601) for optimum focus on the dot pattern screen.