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Marconi, that model demonstrates the limitations with widening the angle very well. Once you begin exposing more of the first 1/4 wave on the vertical radiator, gain on the horizon goes down while gain in the 40 degree range goes up. That also happens ten fold once you sweep the radials out at 90 degrees or down on a 45.

It should also be pointed out a lot of this work is difficult and easily led astray. It's a labor of love to try and find any way to improve antennas and I'm by no means perfect. Case in point was following through with Avanti's suggestion in the patent that a wider angle would produce improved gain. You saw I built the antenna and even had it tuned to the point it led me to believe there were improvements as I once reported.

In the long run, the idea failed and the discrepancy in the field tests were traced back to deficiencies in the receiver being used to peak the gain. While gain in transmit is reciprocal to gain in RX on nearly all antennas, troubles can easily arise when you discover the input impedance on nearly every HF receiver is far from 50 ohms. That makes a huge difference when tuning for gain in what you assumed was a 50 ohm match. It took a network analyzer and some receiver work to correct that issue.

<blockquote data-quote="Shockwave" data-source="post: 385009" data-attributes="member: 10882">Marconi, that model demonstrates the limitations with widening the angle very well. Once you begin exposing more of the first 1/4 wave on the vertical radiator, gain on the horizon goes down while gain in the 40 degree range goes up. That also happens ten fold once you sweep the radials out at 90 degrees or down on a 45.It should also be pointed out a lot of this work is difficult and easily led astray. It&#039;s a labor of love to try and find any way to improve antennas and I&#039;m by no means perfect. Case in point was following through with Avanti&#039;s suggestion in the patent that a wider angle would produce improved gain. You saw I built the antenna and even had it tuned to the point it led me to believe there were improvements as I once reported.In the long run, the idea failed and the discrepancy in the field tests were traced back to deficiencies in the receiver being used to peak the gain. While gain in transmit is reciprocal to gain in RX on nearly all antennas, troubles can easily arise when you discover the input impedance on nearly every HF receiver is far from 50 ohms. That makes a huge difference when tuning for gain in what you assumed was a 50 ohm match. It took a network analyzer and some receiver work to correct that issue.</blockquote>

[QUOTE="Shockwave, post: 385009, member: 10882"] Marconi, that model demonstrates the limitations with widening the angle very well. Once you begin exposing more of the first 1/4 wave on the vertical radiator, gain on the horizon goes down while gain in the 40 degree range goes up. That also happens ten fold once you sweep the radials out at 90 degrees or down on a 45. It should also be pointed out a lot of this work is difficult and easily led astray. It's a labor of love to try and find any way to improve antennas and I'm by no means perfect. Case in point was following through with Avanti's suggestion in the patent that a wider angle would produce improved gain. You saw I built the antenna and even had it tuned to the point it led me to believe there were improvements as I once reported. In the long run, the idea failed and the discrepancy in the field tests were traced back to deficiencies in the receiver being used to peak the gain. While gain in transmit is reciprocal to gain in RX on nearly all antennas, troubles can easily arise when you discover the input impedance on nearly every HF receiver is far from 50 ohms. That makes a huge difference when tuning for gain in what you assumed was a 50 ohm match. It took a network analyzer and some receiver work to correct that issue. [/QUOTE]

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