Patent ID: 6754476
Filing Date: 2004-06-22
Classification: H03G

Abstract:
A portable radio transmitter, comprising:a voltage signal generator including an oscillator for generating an AC voltage signal; a power-adjustable amplifier circuit for amplifying said AC voltage signal to generate an amplified AC voltage signal, said amplifier circuit including at least one bipolar transistor having a base electrode connected to said oscillator; a power-regulating circuit including an operational amplifier having two inputs, and an output which provides a power-regulating setting signal to said at least one transistor through a current-setting element, wherein one of said two inputs is connected to a power setting voltage; a rectifier stage supplied with a feed back voltage signal, wherein said rectifier stage includes a pair of diodes connected in parallel, in opposite directions, with one of said diodes being connected in parallel with a combination of a capacitor and a first resistor and said one diode also being coupled to another one of said two inputs of said operational amplifier; and a radio-transmitting antenna receiving said amplified AC voltage signal.