Yaesu FT-7 is a rugged, solid state and modular built HF amateur-band 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 20 W.
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 10m band coverage in four 500kHz segments (this was limited to a single 500kHz segment in the original FT-7 version).[1][2] The FT-7B also offers Amplitude modulation (AM) mode. Its transmitting output is adjustable from 5 to 50 W maximum by an integrated 50 W power amplifier using two 2SC2099 final transistors. It is also equipped with a noise blanker and an RF attenuator.
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 3 W 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.
Accessories
VF-7 separate VFO (and only for FT-7);
YC-7B digital readout frequency counter (and only for FT-7B);
FL-110 linear amplifier 10 W in, 90 W out;
RSL/RSM mobile HF antenna combination consisting of the RSM chassis clamp and 5 antennas for the 80, 40, 20, 15 and 10m amateur bands.
FT-7 specifications
Frequency coverage: 3.5 -4.0, 7.0-7.5, 14.0 – 14.5, 21.0 – 21.5 and 28.5 – 29.0MHz
Power supply: 13.5 V DC @ 3 A transmit; 0.4 A receive
Dimensions: 23×8×29cm
Weight: 5kg
Emission: LSB, USB, CW Power input: 30 W DC
Carrier suppression: better than 50dB below rated output
Unwanted sideband suppression: better than 50dB @ 1000Hz
Spurious: better than – 40dB Distortion: better than -31dB
Transmitter freq response: 350 – 2700Hz (-6dB)
Stability: less than 300Hz drift from cold start, less than 100Hz drift after 30 mins warmup
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