Just as a starting point, NEC2 was used to calculate the feed point impedance of an inverted V antenna, with a 30 degree droop, with the apex 10 meters above finite ground (epsilon=15, sigma = .005), and 5 meter long legs (this happens to resonate around 14.6 MHz).
Here's the impedance as a function of frequency
And, a file you can download: vz.txt
Raw data zvdatin.txt
antenna/zdipolev.htm - 11 August 2003 - Jim
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