Hitachi CM615ET, Руководство по обслуживанию

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4. OPERATION THEOREM
A. Power Supply:
Transfer AC source to DC source that supply all the circuit power. It includes:
(1) +12V: For video pre-amp circuit, parts of horizontal and vertical deflection circuit.
(2) +180V: For deflection and H.V circuit
(3) +7.5V: For CRT heater and u-P power.
(4) +75V: For video AMP. Circuit.
(5) +42V: For vertical deflection and Horizontal predriver .
(6) +16V: For vertical preampifier
B. Deflection:
Produce YOKE deflection current of horizontal and vertical, CRT H.V and bias that makes screen raster.
C. Video
Amplify the video signal and add the signal to the cathode of CRT to produce video on the screen.
D. Digital Controllor
With the EEPROM and PROGRAM, the micro-processor(u-P) control all the picture performance.
From the key control, the user can change the H-size, V-size, R-gain.…etc.