Position: Index > Transmitter Circuit >

FIBER_OPTIC_TRANSMITTER

2016-04-08 21:45  
Declaration:We aim to transmit more information by carrying articles . We will delete it soon, if we are involved in the problems of article content ,copyright or other problems.


FIBER_OPTIC_TRANSMITTER
This receiver circuit consists of wideband differential amplifier NE592, VCO NE564 and LED driver NE522-the high-speed comparator. The video signal is ac coupled into the modulator preamplifier and followed by a sync tip clamp to provide dc restoration on the composite video signal and to prevent variation of modulation deviation with varying picture content. A video signal level of 250 to 300 mV peak is required to maintain optimum picture modulation. Frequency compensation (preemphasis) is inserted in the form of a passive rc lead network at the input to the NE592 differential amplifier. The main FM modulator consists of an NE564 used only as a linear wideband VCO, but the other sections of the device are not used. Differential dc coupling to the VCO terminals is attained via the loop filter terminals, pins 4 and 5.