| 摘要 |
A radio frequency transmitter, amplitude modulated, having a single tuner that tunes the frequency oscillator, the isolating filter and the antenna impedance, all at the same time. The transmitter includes a tunable carrier generator for generating a carrier signal of a desired frequency, and a carrier isolator for filtering the carrier signal so as to ensure a clean, isolated carrier signal. A power amplifier is included for amplifying the signal from the carrier isolator. The power amplifier has a certain output impedance. An antenna is connected for transmitting the amplified signal from the power amplifier. The antenna also has a certain impedance. The transmitter further includes an impedance matching device connected between the antenna and the power amplifier for matching the antenna impedance and the power amplifier impedance. Finally, a single control knob is provided for simultaneously controlling the tunable carrier generator, the carrier isolator and the impedance matching device. Thus, any particular setting of this control knob corresponds to a predetermined value of each of the tunable carrier generator, the carrier isolator and the impedance matching device.
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