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Different manufacturers have experimented with the length of this design, building models anywhere from 27 to about 30 feet in length on 11 meters. They have obviously noticed the same characteristics I see in field testing, that the length of this radiator is has a bigger impact on focusing the pattern on the distant horizon than other antennas with a single radiation point.

With both the cone and the top section radiating, the length of the whip and cone also controls the phase delay to the top section. Altering that phase delay between the two sections, allows you to introduce "electronic beam tilt". On 11 meters, our antennas are relatively close to the ground in terms of wavelength and these variables in height also determine what length provides the most effective beam tilt and target area for your location.

On VHF, most antennas are usually mounted many wavelengths above ground and that reduces the effect that changes in height have on the take off angle. That also allows one length of antenna to fit more applications than we might see on 11 meters where antenna height is typically much closer to the wavelength in use and therefore, has a larger impact on TOA.

I've honestly never tested the design in the field without a mast or with an isolated mast. What I can tell you is when the antenna is not properly tuned, it will show CMC on the coax and mast. Changes in the length of either one can show changes in the amount of reflected power at that point. Once the antenna is tuned to 50 ohms, none of this is noticeable anymore.

<blockquote data-quote="Shockwave" data-source="post: 699933" data-attributes="member: 10882">Different manufacturers have experimented with the length of this design, building models anywhere from 27 to about 30 feet in length on 11 meters. They have obviously noticed the same characteristics I see in field testing, that the length of this radiator is has a bigger impact on focusing the pattern on the distant horizon than other antennas with a single radiation point.With both the cone and the top section radiating, the length of the whip and cone also controls the phase delay to the top section. Altering that phase delay between the two sections, allows you to introduce &quot;electronic beam tilt&quot;. On 11 meters, our antennas are relatively close to the ground in terms of wavelength and these variables in height also determine what length provides the most effective beam tilt and target area for your location.On VHF, most antennas are usually mounted many wavelengths above ground and that reduces the effect that changes in height have on the take off angle. That also allows one length of antenna to fit more applications than we might see on 11 meters where antenna height is typically much closer to the wavelength in use and therefore, has a larger impact on TOA.I&#039;ve honestly never tested the design in the field without a mast or with an isolated mast. What I can tell you is when the antenna is not properly tuned, it will show CMC on the coax and mast. Changes in the length of either one can show changes in the amount of reflected power at that point. Once the antenna is tuned to 50 ohms, none of this is noticeable anymore.</blockquote>

[QUOTE="Shockwave, post: 699933, member: 10882"] Different manufacturers have experimented with the length of this design, building models anywhere from 27 to about 30 feet in length on 11 meters. They have obviously noticed the same characteristics I see in field testing, that the length of this radiator is has a bigger impact on focusing the pattern on the distant horizon than other antennas with a single radiation point. With both the cone and the top section radiating, the length of the whip and cone also controls the phase delay to the top section. Altering that phase delay between the two sections, allows you to introduce "electronic beam tilt". On 11 meters, our antennas are relatively close to the ground in terms of wavelength and these variables in height also determine what length provides the most effective beam tilt and target area for your location. On VHF, most antennas are usually mounted many wavelengths above ground and that reduces the effect that changes in height have on the take off angle. That also allows one length of antenna to fit more applications than we might see on 11 meters where antenna height is typically much closer to the wavelength in use and therefore, has a larger impact on TOA. I've honestly never tested the design in the field without a mast or with an isolated mast. What I can tell you is when the antenna is not properly tuned, it will show CMC on the coax and mast. Changes in the length of either one can show changes in the amount of reflected power at that point. Once the antenna is tuned to 50 ohms, none of this is noticeable anymore. [/QUOTE]

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