HF tuned aerial with variable magnetic coupling and line impedance - uses flexible rod with knob at one end and nut holding insulating tube at other

摘要

A h.f. tuned aerial has variable magnetic couplings on opposite ends. The aerial converts frequencies or waves in a cable into a h.f. oscillation or vice versa. The impedance of the transmission line can be adjusted to achieve a match with the aerial. The aerial is designed so that it is not be subject to any frequency changes due to external effects. The aerial consists of a flexible rod with a knob pressed onto the upper end. An insulating tube (14) is fitted to the lower end which is attached to a nut. The vibrating length of the aerial is smaller than a whole number fraction of the wave length of the highest frequency of the band. There is a coil attached to one end with a conductor in the magnetic field of the coil. The magnetic coupling between the coil and the field can be varied.