VARACTOR FREQUENCY MULTIPLIER 400 MHZ
Varactor frequency multipliers have found wide application in signal generation devices of transmitters and receiver heterodynes. With their help, it is possible to obtain a highly stable signal in those frequency bands where direct generation is impossible or difficult, and therefore their investigation is actual [1-12].The following requirements are imposed on the frequency multiplier:- input frequency of 400 MHz;- multiplicity of frequency multiplication from 2 to 9;- input power from 10 to 20 dBm;- transmission ratio from 10 to 20 dB;- input resistance 50 Ohm;- load resistance 50 Ohm;- input and output connectors are type 9 according to GOST 13317-89.Such parameters can be realized in frequency multipliers on varactors, diodes with accumula-tion of charge, on transistors and microcircuits. In this paper, a variant of the varactor frequency multiplier is chosen because of its simplicity and lack of supply voltage.An experimental study of a varactor frequency multiplier is performed when a signal with a frequency of 400 MHz is applied to the input. Amplitude characteristics are obtained for multi-plicities of multiplication of frequencies from two to nine. A schematic diagram of the frequency multiplier, a brief description of the design, and the experimental procedure are presented.Widely used parallel and sequential scheme of the inclusion of the varactor. In this case, the parallel inclusion of the varactor is used. The U-shaped link of the low-pass filter is used for to match the input resistance of the frequency multiplier with the wave impedance of the path.It is shown that acceptable output power levels from minus 8 dBm to 4 dBm are obtained on harmonics from the second to the ninth with an input power of 20 dBm. In this case, the transmis-sion factor varies from minus 30 dB to minus 20 dB.