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9212 divided by frequency in MHz. is the length from tip to connector. The cone support rods are 1/4 wave and the entire length around the loop is also 1/4 wave. Adjust the gamma for VSWR, not the radiator length. These measurements have replaced a lot of 1/2 wave side mounted antennas in my field over the decades. Side mounting gives the dipole nearly a 2db advantage on its strongest side. Adding less than 10% more height in order to top mount this design does not add 2db. However, the coverage is equal to or greater than that of the dipole in its strongest direction but, in a perfect omni pattern.

In some cases we even lost a few feet of height when the dipole was side mounted to a mast already at the top of the tower. When you're at least 100 feet AGL on VHF, several feet either way doesn't make a difference, it all comes down to the gain being focused on the distant horizon. While many people test antennas, few have had the opportunity to compare this design against as many unity gain 1/2 wave dipoles, while virtually eliminating all other variables. It is not uncommon for these stations to reconfirm their 60dbu coverage area after an antenna and TPO change in order to insure compliance with regards to adjacent channel interference guidelines they may be subjected to. Just renting that calibrated field strength receiver for the day has cost some nearly $1,000.

<blockquote data-quote="Shockwave" data-source="post: 699729" data-attributes="member: 10882">9212 divided by frequency in MHz. is the length from tip to connector. The cone support rods are 1/4 wave and the entire length around the loop is also 1/4 wave. Adjust the gamma for VSWR, not the radiator length. These measurements have replaced a lot of 1/2 wave side mounted antennas in my field over the decades. Side mounting gives the dipole nearly a 2db advantage on its strongest side. Adding less than 10% more height in order to top mount this design does not add 2db. However, the coverage is equal to or greater than that of the dipole in its strongest direction but, in a perfect omni pattern. In some cases we even lost a few feet of height when the dipole was side mounted to a mast already at the top of the tower. When you&#039;re at least 100 feet AGL on VHF, several feet either way doesn&#039;t make a difference, it all comes down to the gain being focused on the distant horizon. While many people test antennas, few have had the opportunity to compare this design against as many unity gain 1/2 wave dipoles, while virtually eliminating all other variables. It is not uncommon for these stations to reconfirm their 60dbu coverage area after an antenna and TPO change in order to insure compliance with regards to adjacent channel interference guidelines they may be subjected to. Just renting that calibrated field strength receiver for the day has cost some nearly $1,000.</blockquote>

[QUOTE="Shockwave, post: 699729, member: 10882"] 9212 divided by frequency in MHz. is the length from tip to connector. The cone support rods are 1/4 wave and the entire length around the loop is also 1/4 wave. Adjust the gamma for VSWR, not the radiator length. These measurements have replaced a lot of 1/2 wave side mounted antennas in my field over the decades. Side mounting gives the dipole nearly a 2db advantage on its strongest side. Adding less than 10% more height in order to top mount this design does not add 2db. However, the coverage is equal to or greater than that of the dipole in its strongest direction but, in a perfect omni pattern. In some cases we even lost a few feet of height when the dipole was side mounted to a mast already at the top of the tower. When you're at least 100 feet AGL on VHF, several feet either way doesn't make a difference, it all comes down to the gain being focused on the distant horizon. While many people test antennas, few have had the opportunity to compare this design against as many unity gain 1/2 wave dipoles, while virtually eliminating all other variables. It is not uncommon for these stations to reconfirm their 60dbu coverage area after an antenna and TPO change in order to insure compliance with regards to adjacent channel interference guidelines they may be subjected to. Just renting that calibrated field strength receiver for the day has cost some nearly $1,000. [/QUOTE]

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