LEARNING REPAIR BLOCK TELEVISION

 Synchronization deflection circuit
This series consists of four blocks, namely: synchronization circuit, a series of vertical deflection, horizontal deflection circuit and high voltage generation circuit.

BLOCK VERTICAL

 

 

BLOCK HORIZONTAL 

chrominance amplifier

This amplifier amplifies the frequency of 4.43 MHz for the chrominance signals are modulated in the signal V (RY signal) and the signal U (BY signal). 2 MHz bandwidth amplifier

 POWER SUPPLY CIRCUIT BLOCK / REGULATOR
 

 Color Sync

In the series sincronisasi color, color sync burst signal is removed from the composite color video signal

 Automatic Color Control (ACC)

If the signal amplitude of the explosion increases, the ACC issued a steering voltage to minimize the reinforcement in the color

Color Killer (which create color)

The circuit is useful for reinforcing oppressive color, if there are no incoming chrominance signal. This happens at the reception of the black-white

 Phase Switching circuit 180 (splitting Color)

Of chrominance amplifier, the signal fed to the color. Splitter (splitting the color). This splitting separates the color signals are modulated by the signal V of the modulated signal with a signal U. Splitting the color of PAL switch and some resistors. At the end of each line, drew a line for PAL then rotated 180 V signal. U signals do not experience a phase rotation

Color Demodulation

Using the color demodulator, then the color difference signals in demodulasikan of signals U and V. Because the transmitter, the signals modulated with suppressed carrier system / sub eliminated and only the second side bearer channels (side band sub-carriers) that exist.
 In order to mendemodulasikannya a carrier signal of the original color back, it would require 4.43 MHz
 sub carrier phase and frequency with the exact same as the transmitter

Here is an explanation of the function of each part:

Antenna: serves to capture the RF signal from a television transmitter.

Tuner: serves to select the wave transmitter to be received.

Contained in the tuner circuit RF amplifier, mixer and oscillator.

RF amplifier in charge of selecting the transmitter to be received and then given to the mixer.

Eventually produce a new frequency mixer, then filtered into two 

frequency are out of the 38.9 MHz and 33.4 MHz.

Frequency of 38.9 MHz picture carrier
 frequency isFrequency of 33.4 MHz 

is the carrier frequency of the sound.Both frequencies are then forwarded to the video IF amplifier.Video IF: function amplifies the signals received from the mixer, and then the video transmitted to the detector.Video detectors: function detects image signals and sound is then passed to the image carrier driver.Sinyal video out image signal detected by the frequency of 15 KHZ-5 MHz, sound carrier signal is detected by the signal out the new sound carrier 5.5 MHz (FM).Video driver serves to separate the sound carrier signal, the image signal and the signal sincronisasi.Image signal is transmitted to the video output.Voice signals transmitted to the sound IF amplifier.Synchronization signal is transmitted to the sync separator.Video output berungsi amplifies the image signal transmitted to the cathode tube.Sound IF amplifier serves to strengthen the voice signal is then transmitted to the FM detector, FM detector detects a signal frequency of 5.5 MHz to live audio, audio amplifier and then to continue to loudspeaker.Untuk to the sound IF amplifier amplifier audio amplifier is as usual.Syncronisasi separator serves to adjust the image emitted from the transmitter.Vertical oscillator frequency of 50 Hz generating function is then forwarded to the output driver and then vertically vertically, next to the vertical deflection and vertical deflection is open the image vertically (top down).AFC function to correct horizontal frequency of 15.625 kHz and forwarded to the horizontal oscillator.Serves to stir the horizontal oscillator frequency 15.625 kHz horizontal and then forwarded to the driver and then to the horizontal output next to the horizontal deflection and horizontal deflection is open the image horizontally (left-right).Horizontal output also generate a high voltage of 10-20 kV to the anode tube.