Abstract: A transmitter is configured to transmit a radio frequency (RF) signal to a receiver. The receiver is configured to receive the RF signal and decode data. Furthermore, a method of wireless communication is provided between the transmitter and the receiver, in which the transmitter transmits to the receiver the RF signal. A carrier phase of the RF signal is randomly converted. The receiver detects an envelope of the RF signal, and extracts data from the RF signal.

Abstract: A high-frequency electron tube power oscillator includes a multi-grid electron tube (1) in which the output power is adjusted by means of an adjustable impedance element (5) connected in series with the cathode line of the tetrode (1). In order to reduce the dissipated power in the adjustable impedance element (5), the voltage across the impedance element is connected to the screen grid of the tetrode (1) through an amplifier (6) constituted by a triode (9) and a current source (10).

Abstract: A Hartley oscillator includes a basic Hartley oscillation circuit having a semiconductor active element, a tank circuit coupled to the active element and having a grounded end, a coupling capacitor connected between the other end of the tank circuit and a control electrode of the active element. A constant direct current source for supplying a constant direct current to an electric current supply terminal of the active element is further provided. A feedback circuit is coupled to the active element and the output of the constant direct current source and adapted to cause a variation of a direct current potential on the current supply terminal of the active element to be fed back to the control electrode of the active element, and a capacitor having a grounded end and the other end connected to the output of the constant current source is further provided in the Hartley oscillator.