The purity of the spectrum of the output signal of the autogenerator has a significant effect on the output signals of the receiving and transmitting equipment. For small-sized mobile transmitting equipment, the parameters of the master generator are crucial in ensuring the main parameters: frequency, power, stability, and the level of parasitic components. The stabilization of the frequency of microwave generators is the most important task in the creation of heterodynes and master generators of radio transmitters. This is especially important when creating receiving and transmitting communication devices, navigation, short-range Doppler radar and radio control. Equally important is the task of stabilizing the frequency of microwave generators in radio measuring equipment. The purpose of the work is to identify parasitic parameters of the microwave generator: frequency run–out, frequency dependence on the gate voltage and drain of the generator transistor, spectrum width, harmonic level of the output frequency. An experimental study of an autogenerator on a field-effect transistor stabilized by a dielectric resonator has been carried out. The schematic diagram of the generator, the calculation of the dielectric resonator, the methodology and the results of the experiment are presented. As the results of the experiment, the frequency run-out curve, the frequency dependence on the supply voltage, and the spectrum of the output signal in the near and far zones are presented. The following results are shown to be achieved: carrier frequency of about 11500 MHz; output power of at least 10 dBm; second harmonic suppression of at least 40 dB; load resistance of 50 ohms; frequency run-out within half an hour 7.8·10−5; frequency change when the gate voltage changes from 5 to 8 V, no more than 14.2 MHz. The parasitic parameters of the generator studied in the work made it possible to identify the influence of various factors on the stability of the frequency of the generator, and make it possible to take measures to improve the parameters. For example, voltage stabilization at the gate will significantly reduce frequency loss, as well as eliminate parasitic amplitude modulation from power source pulsations. In modern power supplies, pulsations can be at a frequency of 100−200 kHz. The studied autogenerator can be widely used as a heterodyne and a master generator in the receiving and transmitting equipment of radio relay communication with frequency modulation, in police radars, in Doppler speed meters of wagons on marshalling yards of railway stations.
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