Hy-gain GRK-88 - Vertical Ground Radial Kit
GROUND RADIAL KIT FOR DX-88 or any vertical Antenna
This is the Ground Radial System for the DX-88 - however it could be used for any vertical antenna as a very efficient ground system.
This radial kit consists of 4 sets of 4 radial wire assemblies (16 total). Each radial is made from7/23 opperweld and is 14 feet (4.3 m) in length. A bracket and U-bolt is supplied for attachment of the radials at ground level.
This permits the radial wires to lie at ground level so that you may mow the grass over the radials,
and not trip over them. Two pigtail wires are supplied to attach the bracket to the base of your own vertical or the Hy-Gain OMNI DX-88 vertical antenna. This ensures a higher conductive path from the antenna base to the radial assembly.
When a vertical is installed on the ground, a radial system is normally required. The minimum recommended radial system consists of 16 radials, each 14 feet (4.3 m) long.
Since the radials of a ground-mounted vertical are actually on, if not in, the ground, they are coupled by capacitance or conduction to the ground, and thus resonance effects are not important. Basically, the function of ground radials is to provide a low-loss return path for ground currents. Longer radials and more
radials will reduce the ground losses and effectively increase the gain of the antenna.
See the article entitled "Radial Systems for Ground-Mounted Vertical Antennas" by Brian Edward, pages 28-30, QST magazine.
The radial length of 14 feet (4.3 m) is approximately 0.1 wavelength a 7 MHz. With poor earth conditions (dry, rocky soil), the gain of this vertical antenna system will be approximately 3 dB below the gain from a
perfect earth or 120 radials. With good earth conditions (agricultural land, low hills), the gain of this vertical antenna system will be approximately 2 dB below the gain from a perfect earth or 120 radials.