Don W7WLL wrote:
>>> Lowering the height of an antenna above ground, such as a beam, will cause
>>> the resonant freq to decrease, increase?
The "Resonate" button of the AutoEZ program makes short work of questions like
this. For example, create a 20m dipole model with an arbitrary length of 33.5
ft at height "H" above ground. Set up a series of test cases with "H" ranging
from 5 to 100 ft, all at 14.2 MHz. Select all the "Freq (MHz)" cells and click
the "Resonate" button. Like so:
http://s33.postimg.org/u5kmyan7j/resonate1.png
Then tab to the Custom chart sheet and plot Frequency on the Y axis vs Variable
H on the X axis. Here are the results for three different EZNEC ground
characteristics.
http://s33.postimg.org/69rm0qscf/resonate2.png
For more examples of using the "Resonate" button see Step 6 here:
http://ac6la.com/autoez.html
Or see the fifth and sixth bullets here:
http://ac6la.com/aecollection2.html
Dan, AC6LA
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