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RedMAX Administration and Maintenance Guide
Redline Communications Inc. Confidential and Proprietary
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Does it have a repetitive pattern?
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Is it sporadic without any relation to a specific channel
Inspect and Repair Lightning Protection System
Ground Connections
A good ground connection is one that has a low resistance to the Earth at radio
frequencies. A ground connection that is good enough for DC or low frequency power lines
(60 Hz) is not necessarily a good ground at radio frequencies.
Figure 4-1shows the most basic form of a radio antenna ground connection. A conductive
ground rod is driven into the Earth for a certain distance. A proper radio ground for high
frequency (HF) band operations should be 8-feet long. Anything less than that usually
results in poor performance, and may not provide proper lightning protection.
Figure 4-1
Radio Antenna Ground Connection
Some ground rods are made of copper, but most are made of copper-clad steel. Such rods
are composed of a steel core with a thin layer of copper on the outer surface. The
low-resistance copper is sufficient for grounding purposes because RF currents flow on the
outside of a conductor (a phenomenon called “skin effect”).
The ground rod in driven into the Earth within a few inches of its top, and then a wire clamp
is fastened. This clamp is used to hold the ground wire securely to the ground rod.