Abstract: A control device for a power amplifier controls the power amplifier upon a rise in output power based on a power variation pattern stored in storage means to suppress a power overshoot which occurs upon a rise in output power.

Abstract: In a portable radio equipment, a first power unit (11) and a second power unit (15) can be selectively mounted to or removed from a radio equipment main unit (1). The main unit contains a transmit audio circuit (3), a first microphone (4), and a power circuit (5). When the first power unit is mounted to the main unit, a short-circuiting member (12) in it connects the first microphone to the transmit audio circuit, and a power source (8A) in it provides power to the power circuit. When the second power unit (15) is mounted to the main unit (1), a second microphone (16) in it is connected to the transmit audio circuit to the main unit, and a power source (8B) provides power to the power circuit.

Abstract: Disclosed is a booster apparatus wherein a detected signal which an input power detecting means outputs is subjected to a fixed processing and made to be a reference voltage for level-setting, and a transmitting level setting means controls the gain of an amplifier in such a manner that a detected signal which a transmitting power detecting means outputs and the reference voltage are balanced with each other.

Abstract: A radio transceiver includes a control section for setting a transmitting output level higher or lower than a prescribed output level within a tolerance range, in response to a signal from a level conversion circuit. The level conversion circuit may designate a lower transmitting output level to reduce power consumption, and may designate a higher transmitting output level in the presence of high noise levels.

Abstract: A road navigation system comprises a plurality of guidance information transmitter systems disposed along a route, each transmitter system generating current location information in the form of extremely-low-powered electric waves, and a guidance signal generator system for providing guidance information for the benefit of a user. The guidance signal generator system comprises a receiver unit for receiving the current location information from the guidance information transmitter system, an input unit for inputting destination information, a memory unit for storing available map information and the inputted destination information which can be prepared as route information to be traced, a data processor unit for comparing the route information with the current location information received by the receiver unit and for producing the guidance information, and an output unit for communicating the guidance information to the user.