Abstract: In a device for use in processing a baseband input signal and a carrier signal into an envelope output signal, a processing unit (3) is supplied with the baseband input signal and the carrier signal and produces, as a produced signal, a modulated signal and a non-modulated signal one at a time in response to a burst control signal. A waveform generating unit (2) is supplied with the burst control signal and generates a control signal. An amplifying unit (4) is supplied with the produced signal and the control signal and amplifies the produced signal to make the envelope output signal represent an envelope of the produced signal and to produce the envelope output signal with an excellent spectrum suppression. Alternatively, the processing unit may be supplied with the control signal instead of the burst control signal.

Abstract: An RF modulator is characterized by a gain adjusting circuit for gain adjustment incorporated with an RF amplifier for amplifying a carrier wave provided from a carrier oscillator and applying the same to a video signal modulator and to an audio signal mixer so that the gain of the RF amplifier is adjustable so as to adjust a difference in level of the carrier wave provided differently depending upon a resonance element being connected to the carrier oscillator.

Abstract: Audio power amplifier in which dynamic power output can be increased without increasing continuous power output. The apparatus includes an amplifying means for receiving an input signal and for producing an amplified output signal, first means for supplying a first, relatively low supply voltage to the amplifying means, second means for supplying a second, relatively high supply voltage to the amplifying means, and control means for supplying the first supply voltage to the amplifying means when the level of the amplified output signal is less than the first supply voltage and for supplying the second supply voltage to the amplifying means when the level of the output signal exceeds the first supply voltage. The invention thus provides an amplifier apparatus having relatively low power dissipation and high efficiency and that will avoid any output signal clipping that will distort the output signal.

Abstract: An improved power amplifier is disclosed which is particularly useful with very high frequency (VHF) transceivers. The power amplifier includes a control loop configured to sense the input radio frequency signal and use that signal as a reference for comparison with the radio frequency output from the amplifier to control amplifier power output. The loop forces the amplifier's output radio frequency envelope to follow the input radio frequency envelope and thus produce a constant gain loop. A limiter in the loop forces the loop to produce a constant power output when the input signal exceeds a level set by the limiter.

Abstract: The present invention relates to a method for automatically regulating the HF output power of a high frequency amplifier wherein a regulating voltage is utilized to produce a control voltage or a control current for controlling the gain of the amplifier, a first voltage which depends on the HF output power is derived from the supply voltage and/or from the supply current of the current supply device providing the power required to generate the HF power; the regulating voltage is formed of two components, with the first component being generated from the first voltage and a first reference voltage, and with the second component being generated from a second voltage which depends on the control voltage or on the control current generated by the control voltage and from a second reference voltage; and that for high HF power essentially only the first regulating component is active and for low and medium power, whose range approximately covers the linear operating range of the amplifier, essentially only the seco

Abstract: The invention relates to a compander system. In such a compander system an adjusting member in the useful signal path is controlled by a control voltage which is generated in a branch path connected to the useful signal path and including at least one further adjusting member. The control voltage serves at the same time to control the adjusting members in the branch path in a counter-regulating sense. According to the present invention the branch path is connected to the input of the useful signal path during compression and to the output of the useful signal path during expansion.

Abstract: An automatic gain control amplifier having a controlled recovery of gain is disclosed and includes a peak detector for generating an output when the amplifier output exceeds a predetermined level, a memory setting circuit responsive to the peak detector output, a memory controlled by the memory setting circuit, and a memory adjust circuit responsive to information derived from the amplifier output. The output of the memory controls an attenuator of the automatic gain control amplifier. Amplifier output level change detection circuitry is also disclosed and accepts the output of the amplifier for producing an output indicating amplifier output level changes exceeding a predetermined magnitude. The level change detection output controls the memory adjust circuit.