Frequency conversion circuit of satellite receiver

In the satellite receiving system, the tuner converts the frequency of the C-band or Ku-band microwave signal received by the satellite antenna and outputs a lower frequency
signal (950~1470 MHz), called the first intermediate frequency signal, which is then sent to the satellite through a coaxial cable. In the second frequency converter of the indoor receiving unit . The signal frequency processed by the second
frequency converter is still very high, and the entire circuit must be made in a well-shielded box to prevent external electromagnetic interference. The function of the second frequency
converter is to reduce the frequency (frequency conversion) and perform tuning at the same time. The signal output by the second intermediate frequency is then subjected to FM frequency discrimination and demodulation , and the video and audio subcarriers modulated on the second
intermediate frequency signal are demodulated. come out.