BUDDIPOLE IN THE FIELD
BUDDIPOLE IN THE FIELD
BUDDIPOLE IN THE FIELD
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17m vertical with 2 radials Far field plot for 17m with 2<br />
radials<br />
Figure 25 17m vertical antenna with 2 elevated radials<br />
If we are only seeing 0.36 dBi of maximum gain, where is the rest of the<br />
energy going? Figure 28 shows this 17m antenna with four radials<br />
deployed over “perfect” ground. When we eliminate ground losses from<br />
the system we get all our power back. The modeling shows the antenna<br />
over “perfect” ground has nearly 6 dBi of gain! Can we get anything<br />
close to that in our deployments? Yes. Saltwater is an excellent<br />
conductor and deploying over saltwater (such as on the beach)<br />
significantly reduces ground losses, losing only 1 dB from the gain over<br />
“perfect” ground. A whole chapter of this book is dedicated to beach<br />
deployments.<br />
Finally, notice the radiation pattern in the saltwater plot in Figure 28.<br />
The angle of maximum radiation is at 10 degrees! Depending on where<br />
in the world you are operating, this might actually be too low, but that is<br />
an easier problem to fix than an antenna that is inefficient, deaf in some<br />
directions, and radiating too high!<br />
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