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Old October 25th 07, 06:07 PM posted to rec.radio.amateur.antenna
Richard Harrison Richard Harrison is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 588
Default Antenna earth stakes - a tricky one!

JERD wrote:
"Does it matter or is good old mother earth still going to provide a
good earth for my antenna system?'

According to B. Whitfield Griffith, Jr. in "Radio-Electronic
Transmission Fundamentals" on page 351, a single ground rod introduces
about 50 ohms to an antenna`s resistance. He says contact resistance to
the soil may be very low but the loss will be in the large area of soil
surrounding the rod. Radials are the answer to the low soil conductivity
probl;em.

A broadcast grounding system of 120 radials, each 1/4-wavelength long,
may have a ground resistance of about one ohm, as shown in Fig. 43-2 on
page 353.

Best regards, Richard Harrison, KB5WZI