Tree Mounted HF Ground Plane Antenna

A tree-mounted, vertically polarized antenna may not be your first choice. Most engineering references do not recommend it, but such an antenna does not cost much, is inconspicuous, and it works.
The idea was described by Chuck Hutchinson, K8CH, in QST for September 1984.

The antenna itself is simple. A piece of RG-58 cable runs to the feed point of the antenna, and is attached to an insulator. Two radial wires are soldered to the coax-line braid at this point. Another piece of wire forms the radiator.

The top of the radiator section is suspended from a tree limb or other convenient support, and in turn supports the rest of the antenna. The dimensions for the antenna are given in the image (click on it to enlarge).

All three wires of the antenna are ¼ wavelength long. This generally limits the usefulness of the antenna for portable operation to 7 MHz and higher bands, as temporary supports higher than 35 or 40 feet are difficult to
come by.

Satisfactory operation might be had on 3.5 MHz with an inverted-L configuration of the radiator, if you can overcome the accompanying difficulty of erecting the antenna at the operating site.

The tree-mounted vertical idea can also be used for fixed station installations to make an invisible antenna.