My 6 and 2 meter antennas ..................................A rare lightning stormin 1999. All of the radios survived
The 6 Meter amateur band runs from 50 Mhz to 54 Mhz. My activity has been nearthe bottom of the band in the SSB segment around 50.125 to 50.200. I have completedhundreds of contacts using a Ten Tec 1208 transverter coupled to a Kenwood TS-120S HF Transceiver, with the whole mess connected to the lower of the two antennas inthe picture above. Using this setup, I have made solid contacts over thousands ofmiles, to areas like the Canadian Maratimes, American Deep South, and Japan. I findit is a lot of fun trying make contacts using low power. This setup is good for about8 watts.
The TS-120S has been modified to work with thetransverter. First, the transverter is designed to operate with an input of about5 watts at a frequency of about 14 Mhz. (actually, the desired operating frequencyminus 36 Mhz.) . The '120 is a 100 watt radio, and controlling the power closelyenough to prevent overdriving the transverter was touchy at best. Another problemwas that the HF signal was getting out into free space, and could be heard for acouple miles. Since the '120 was not to be used on HF, I removed the final amplifierstage, and drive the transverter with the driver stage of the '120.; This appliesabout 100 mw, which is not enough. Solution? I removed the attenuater in the transverterand VIOLA! The Ten Tec transverter is rated at about 8 watts out, and this levelof drive is just right.
The Ten Tec 1208 transverter was built from a kitin 1997. It works well, with one exception. As designed, the unit switches fromRX to TX by sensing the transmitter RF. The problem I had was that the unit didn'tswitch to transmit until after one or two syllables had been spoken, so they werenot transmitted. The solution? I used the accessory jack on the '120 to turn ona relay the instant the microphone button is pressed. The relay contacts are acrossthe TX/RX switch in the '1208. No more dropped syllables.
One other commenton the '1208. It doesn't like low DC voltage. with 12.0 volts, the power dropsoff sharply, and distortion goes up a lot. At 13 volts, it's perfect.
Theantenna is a homebrew, constructed from old channel 2 TV antennas, modified to approximatea 4 element 6 meter yagi described in The ARRL Antenna Book, 16th edition. Usinga gamma match, the SWR is about 1.2:1 at 50.125Mhz. The 6 meter antenna is about25 feet above the ground, and about 5 feet below the 2 meter yagi. The antenna isabout 12 years old. I'm a little surprised it's still in one piece.
Link to the American Radio Relay League
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