Yaesu FT-707 (S)

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The Yaesu FT-707 is an HF transceiver for the 80-40-30-20-15-17-12 and 10 meter radio amateur bands. Its construction is based on a metal-cased transceiver with a dicast aluminium front. The rig can handle the AM, CW and SSB modes on the above-mentioned bands and has no general frequency coverage receive options. As a real 1970’s piece of equipment the FT-707 is equipped with numerous whistles and bells displaying a LED ‘lightshow’ in case they are all activated. Its frequency readout is available in a traditional analog (dish) mode as well as in a large digital display mode.

FT-707 was released in 1976 by the Japanese Yaesu Musen Corporation for appx $ 400 as a ‘compact size’ rig. This type was in production until 1979 and available as FT-707 (100 watt output) and as FT-707S (10 watt output) QRP version.

Technical description[edit]

The receiver front end uses a Schottky barrier diode ring module and by means of a developed gain distribution module this results in very good performance in the presence of strong signals. The lownoise premix local oscillator optimizes its receiving performance. Two 8 pole IF filters allow a continuously variable IF bandwidth and 6 pole optional filters are available for demanding operators.

The transmitter output is being generated by 2 multiple protected bipolar 2SC2290 and 2SC 2395 transistors. Final stage protection is included and band switched lowpass filters provide interference protection.

Accessories[edit]

  • FC-707 antenna tuner unit
  • FP-707 integrated AC power supply / speaker unit
  • FV-707 external analog VFO unit
  • MH-1B, YM-35/36/37 hand mikes
  • XM-455 C/A/S CW, AM, SSB filters
  • YM-34 desk mike
  • Metal rack mount

Pros[edit]

Even nowadays nice looking. Reasonable transmitting and receiving results. Nice digital readout display. Very clean tx audio. Accessories are regularly second hand available.

Cons[edit]

The set is out of production for a long time so keep in mind that obtaining (new)spare parts will not be easy. Well known FT-707 problems are the band switches (almost no replacements available). The R/T relay is often subject to malfunction as well as worn out up/dwn push buttons. Sometimes the SWR protection circuit fails. It drifts sometimes. Weak rx audio because of collapsible strut mount and downwards facing internal speaker. (Actually, the radio has very good RX. The author is making reference to the downward facing speaker, and possible audio degradation thereof. Use either an external speaker, preferred, or use the wire stand underneath the front of the radio. The factory supplied speaker is quite good.)

Tech Specs[edit]

  • Frequency range: 80,40,30,20,17,15,12,10 amateur bands (TX and RX)
  • Operational modes: AM, CW, USB, LSB
  • Transmitter input: AM 80W DC; SSB 240W DC
  • Transmitter output: AM 50W; SSB 100W
  • Carrier suppression: better than 35 dB
  • Unwanted sideband suppression: better than 50 dB @ 14MHz, 1kHz mod
  • Spurious: at least – 50 dB
  • 3rd order distortion products: at least – 30 dB
  • Stability: less than 300Hz from 0-30min after start up
  • Receive sensitivity: 25 mV/10db S/N SSB/CW; 1mV/10dB S/N AM
  • Selectivity:
    • SSB, 2.4kHz-6 dB, 4.0kHz-60 dB
    • CW, 0.6kHz-6 dB, 1.2kHz-60 dB
    • AM, 3.6kHz-6 dB, 6.8kHz-60 dB
  • Image rejection: 80-12m 60 dB, 10m 50 dB
  • Antenna: 50Ohm balanced
  • Audio output imp: 4 – 16Ohm
  • Audio output: 3W for 4Ohm @ 10% THD
  • Bandwidth control: continuously variable 300Hz– 2.4kHz(SSB)
  • Power requirements: 13.8V DC neg ground
  • Current consumption: Rx–DC 1.5A; Tx–DC 20A
  • Dimensions: 9.5 x 24 x 29.5cm with rear heat sink
  • Weight: 6.5kg

External links[edit]

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