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Long antenna for a short lot

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Many amateurs don't operate on the lower frequencies because the size of a city lot does not permit the erection of suitable antennas. The antenna described here permits operation on 80 meters even though space may be limited.

Fig. 1A shows the physical arrangement of the antenna. A wire 67 feet long extends from a pole (my pole is 25 feet high) to a connection on the antenna tuner. A second wire, also connected to the tuner, drops from the shack to a pair of stakes where it is supported a foot or so above the ground. This second wire, of some random length, is positioned directly under the top wire.

Fig 1
Fig. 1. A) W3NUG's low frequency antenna;
B) circuit of the antenna tuner for 80 meters;
C) circuit of the antenna tuner for 40 meters.

The circuit for this antenna arrangement is shown in Fig. 1B. Capacitor C1 resonates the antenna to the desired operating frequency while the inductance L1 acts as a loading coil to compensate for the shortage in length of the lower wire. It also provides a means of coupling the antenna system to the transmitter. For operation on 40 meters the antenna should be connected as shown in Fig. 1C. Capacitor C1 should have a plate spacing similar to that of the plate tank capacitor in the transmitter.

William G. Walker, W3NUG.