Radio set

摘要

A radio set comprises an antenna which is a lambd/2 monopole antenna capacitively coupled to the radio circuit on a circuit substrate by way of a capacitor and powered by the circuit. A ground pattern is formed on the circuit substrate in a region of about lambd/2 at the side of the antenna as viewed in the axial direction of the antenna and another ground pattern is formed in the remaining region of about lambd/2 and electrically connected to the ground pattern by way of an inductor. The inductance of the inductor is so selected that the phase of the electric current flowing between the ground pattern and the ground pattern is advanced by 180° at the operating frequency of the wavelength lambd.