Yaesu FT-101

The Yaesu FT-101 is a model line of modular amateur radio transceivers, built by the Yaesu Corporation in Japan during the 1970s and 1980's.

Technical description

The FT-101 is a hybrid radio that employs a solid state transmitter, receiver, and a tube final amplifier. The tube amplifier consists of a 12BY7A pre-driver stage that feeds a pair of 6JS6C tubes providing a nominal output power of 130 watts peak-envelope-power (PEP) single sideband (SSB), 90 watts CW, 40 watts AM. The 6JS6C tubes are matched to 50 ohms through a conventional pi-output network. The pi-network transforms the 3000 ohm output impedance of the tubes to a 50 ohm feed system, provides harmonic attenuation, and can actually match to a variety of output impedances from 25 to 100 ohms.

The transceivers were made with plug-in boards that could be sent to the factory for replacement or repair. This modular design was unprecedented in the amateur community, which explains why so many FT-101's are still in use today. The unit was made almost entirely of metal. Covers, chassis, shields, shafts, etc., are all metal. Even the plastic RF/S-meter trim and knobs have brass metal inserts. The 10 major circuit boards are mounted with threaded hardware to the main chassis. The unit weighs 35 lb (16 kg).

Performance specifications

The unit can receive from 10.0-10.5 MHz in order for recepetion of the WWV time and frequency standards. The unit could transmit and receive on the 160 m, 80 m, 40 m, 20 m, 15 m, and 10 m amateur radio bands. WARC band coverage is possible using aftermarket kits. Early models included the once active 11 m band. Although later models dropped the 11 m position, upgrades were available (and are often used by citizens' band (CB) operators to achieve illegal power outputs in the adjacent CB band). The B, E, and F trimlines (discussed below) include reception and transmission on the 160 m band, as well.

The unit can modulate using either upper sideband (USB), lower sideband (LSB), continuous wave (Morse Code), or amplitude modulation (AM). The power available in these modes is 130 W (SSB), 90 W (CW) and 40 W (AM). The standard audio-frequency filter used for transmission passed 300 Hz to 2700 Hz.

Many station accessories were available including: the FV-101B external VFO, SP-101 & Landliner speaker/phone patch, YO-100 & YO-101 series monitor scopes, YC-601 digital display unit along with the model FTV-650 six and model FTV-250 two meter transverters.

Trimlines

Albert Rabassa (call sign NW2M) has compiled the following information concerning the various FT-101 designs, based on available features:

*FT-101 "Early" having serial number below 25000, including Mark 0 (-06000), Mark 0A (06001-07991), Mark I (08000-23999), Mark II (24000-24999)
*FT-101 "Late" Mark IIA (25000+)
*FT-101B "Early" (-6000)
*FT-101B "Late" (6000+)
*FT-101BS
*FT-101E
*FT-101EE
*FT-101EX
*FT-101ES
*FT-101F
*FT-101FE
*FT-101FX
*FT-101Z
*FT-101ZD, which transitioned through the addition of the WARCdn amateur bands

History and lore

Because critical circuit designs were kept to a manageable size, hams had no problem in offering circuit changes, isolating and repairing problems. This knowledge base was so active that in January 1972, Milton Lowens (call sign WA2AOQ), founded the International Fox Tango Club and the Fox Tango Newsletter. The Fox Tango Newsletters were published for 14 years covering the early FT-101's through the latest Yaesu Transceivers in 1985.

External links

* [http://www.qsl.net/nw2m/ft101.html NW2M's page] at [http://www.qsl.net qsl.net]
* [http://www.foxtango.org The Fox-Tango Web Site]