Short range 3.5mhz radio direction finder

Abstract

The invention relates to a short-distance 3.5MHz radio direction finding machine, which includes a casing and a control circuit arranged in the casing. The control circuit includes a direction-finding antenna, a high-frequency amplification unit, an adjustable beat oscillator, a difference frequency detection unit and The audio amplifying unit, the direction finding antenna is connected to the input end of the high frequency amplifying unit, the output end of the high frequency amplifying unit and the output end of the adjustable beat oscillator are respectively connected to the input end of the difference frequency detection unit, and the difference frequency detection unit The output end is connected with the input end of the audio amplifier unit, and the output end of the audio amplifier unit is connected with the earphone interface. The present invention only uses an adjustable beating oscillator to directly send out low-frequency signals, and at the same time play the role of channel selection and beating, omitting the intermediate frequency conversion and processing circuit, simple circuit, flexible use, strong radio receiving ability, suitable for use in mountainous areas, etc. It is used for competitions in special environments and has a wide range of applications, meeting the needs of radio direction finding sports in various environments.

Description

technical field [0001] The invention relates to a radio direction finder, in particular to a short-distance 3.5MHz radio direction finder. Background technique [0002] The radio direction finding movement was developed on the basis of the extensive amateur communication carried out by radio amateurs. The radio direction finding competition is very interesting. It is like playing a game of hide and seek. The athletes are busy listening, running, and searching for hidden radio stations in the mountains and fields. The radio direction finding competition is also very mysterious. The competition area is kept secret, and the location of the radio station is kept secret. Athletes think and move independently during the competition. They cannot receive the guidance of the coaches, and they are not allowed to accept any help and hints from anyone. Only the radio direction finding machine is used. He is a faithful partner of the athlete. The athlete uses a radio direction finder in...

AI Technical Summary

Problems solved by technology

[0004] The invention mainly solves the technical problems that the circuit structure of the original radio direction finding machine is complicated, the radio receiving ability is relatively limited, it is not suitable for competitions in special environments such as mountains, and the scope of use is relatively limited; it provides a short-distance 3.5MHz radio direction finding The machine has a simple circuit and strong radio receiving ability. It is suitable for competitions in special environments such as mountains. It has a wide range of applications and meets the needs of radio direction finding sports in various environments.

Images