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Antenna system at WB2RCB

Below left: My present day antenna farm consists of a Rohn FK2558 foldover tower using a 4-point guying system. Atop the tower is a Hy-Gain TH3MKII tribander that I have had since 1966. It has been rebuilt 3 times over 40 years and still delivers excellent performance. It is rotated by a Hy-Gain Ham IV rotator. Also mounted on the tower are full wave loops for 40 and 80 meters fed thru 75 ohm 1/4 wave matching transformers along with a inverted-L for 160 meters fed thru a motorized base matching capacitor.

Below right: Antenna switching is carried out by the unit pictured below. I built this one from an article in QST. It effectively grounds all antenna's and control cables when the power is removed from the unit. It uses heavy duty Potter& Brumfield PRD-11DYO-24 wide spaced contact relay's. Everything is housed in a Hoffman waterproof enclosure. All cables entering the enclosure are routed thru bulkhead connectors that have sealed gaskets to prevent moisture from entering. This unit is used to select either the 75 or 40 meter Delta loop's, the 160 meter Inverted L or the tribander. I would highly recommend this switchbox to anyone needing a heavy duty unit. It was engineered and constructed by W5AN and the article appeared in QST in August of 1997. This photo was taken prior to completion.
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Above left: A Heathkit SA-2550 motorized matching capacitor for the 160 meter inverted-L antenna which is controlled from the shack. With this unit it is possible to match the antenna any place in the 160 meter band with a flat 1:1 SWR   Currently I have 40 resonate (125') radials bonded to the round aluminum plate which in turn is connected to the 2" copper pipe which is sunk 8 feet in the ground. The SA-2550 capacitor is insulated from the pipe using a 1/2" thick PVC plate.

Above right: 1/4 wave matching transformers for the 40 and 80 meter full wave loops. Also shown is the antenna selection relay box and the Heathkit SA-2550 matching capacitor.


From the archives

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Above left: Here is the Hy-Gain TH3MKII tribander after completing the installation at my dad's house in 1966. Even though the beam was only up at 31 feet, it performed admirably and gave me hours of enjoyment. I'm still using this antenna today after surviving two additional moves and the "Ice Storm" of 1991

Above right: The devastating northeast "Ice Storm" of 1991 laid down a coating of ice on the antenna's that measured 2-1/2" thick. Moments before this picture was taken, the Diamond X-500 vhf/uhf vertical above the tribander was curled over 90 degrees. I never thought that all of the antenna's would survive this abuse and still return to their original state. Although the X-500 is not presently on the tower, all antenna's including the two full wave loop's did survive and are in use today.