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enhance weather resistance, place a bead of non-corrosive, marine grade silicone along the seams
where the two halves of the case meet. Leave small openings in the two bottom seams to allow any
condensation to drain.
Do not use sealants that have a vinegar-like smell because they contain acetic acid which will
corrode aluminum. Recommended sealant is the
UMI-82180 - Approved RTV Sealant
.
Providing a Good RF Ground
This active vertical antenna works well with just a single copper ground rod used as the mounting
rod.
You can test ground quality by listening to a steady local signal. Attach 15 feet of wire laid in a
straight line away from the coaxial feedline. If you observe a change in signal or noise level, you
need to improve the ground. A second rod spaced a few feet away from, and connected the first one
may correct the problem. If a good ground cannot be established, use a
DXE-RFCC-1
Feedline
Current Choke that will further decouple the feedline from the antenna and reduce common mode
current and associated noise from the feedline.
If you want to locate your ground mounted antenna where ground rods cannot be used effectively,
you must use a radial system or metal ground screen. A suitable radial system consists of four to
twelve equally spaced radials, with each radial being at least 15 feet long.
Only if the antenna is located over rock, on a roof, or otherwise installed where conductive soil
conditions do not exist, you must use a ground screen. Welded-wire galvanized screens are okay for
this receive antenna only and are not recommended for transmit antennas. Screen radius must at least
equal the element height and be placed around the antenna as symmetrically as possible.
Do not use elevated radials or grossly asymmetrical radial configurations. The ground system is an
integral part of this receiving system, and if it is asymmetrical or exhibits pronounced resonances,
the antenna system may not function properly.
Rear View Front View
