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. Yaesu FT-7 is a rugged, solid state and modular built HF amateurband radio transceiver, suitable for fixed and for mobile operation. The set was built by the ''Yaesu Corporation'' in Japan in the late 1970s and early 1980s. Its first Japanese release was in 1976. This transceiver was very small for its time; by current modern standards however it is a large mobile set. It is a low-power (QRP) SSB and CW transceiver of which transmitting power is adjustable up from 10 to about 20W. The set is built up with pre-dated synthesisers and microprocessors, has an excellent receiver and a perfect dynamic range with good close-in noise performance which makes tuning across the noisy 80 or 40m bands at night very easy. All features, coupled to a price of $260- (in 1976) made sure that the "Fox Tango 7" as it was known became very popular in the HAM world. In 1979 its somewhat upgraded successor – the Yaesu FT-7B – was released and as of 1980 this rig was also sold on the European market. FT-7B has fully extended 10 m band coverage in four 500 kHz segments (this was limited to a single 500 kHz segment in the original FT-7 version). The FT-7B also offers Amplitude Modulation (AM) mode. Its transmitting output is adjustable from 5 to 50W maximum by an integrated 50W power amplifier using two 2SC2099 final transistors. It is also equipped with a noise blanker and an RF attenuator. It is a compliment to its manufacturers that even nowadays more than 30 years later FT-7(B)’s are still popular and are often used as a secondary or as a back-up transceiver. In Europe the sets were imported by the Swiss firm ''Sommerkamp'' and sold as Sommerkamp FT-7(B). == Technical description == Solid state receive and transmit operating in single conversion configuration with premix heterodyne techniques reducing signal distortion in transmit and receive mode. The incoming signal goes via an antenna relay, tuning circuit, to a RF amplifier, passband tuning unit and mixer. The signal is filtered and fed to the audio amplifier and translated into a 3W audio signal. The outgoing signal is going from the microphone via the modulator / demodulator unit to a filter. Then it is amplified and heterodyned, mixed and fed to the final amplifier. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Yaesu FT-7(B)」の詳細全文を読む スポンサード リンク
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