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You have to read his entire article on this topic, not just the parts someone else quoted from his links. Someone posted the original links on this site to Tom's site and I spent some time reading the whole thing. He does step back from the comments quoted here and basically contradicts himself saying that the 5/8 wave is not worse then the 1/4 wave but that there are examples of where the 1/4 can equal the 5/8 wave. The real point Tom is trying to make deals with "reliability" and how that relates to many variables with the 5/8 wave. This requires a good understanding of typical radiation patterns of the antennas in question. Dealling with how the groundplane radials and height above ground will impact the secondary lobes, their beamwidth, and the elevation angle of the primary lobe that's hopefully on the horizon.

W8JI is saying that the 5/8 wave depends heavily on a good groundplane under the vertical and that its narrower beamwidth will be more affected by height above ground. The 1/4 wave also needs its groundplane under the vertical and its peak elevation angle will change with height too. The big difference is when you have the huge beamwidth of the 1/4 wave, you're literally sending out a radiation pattern that looks like a big ball in free space. That increases reliability by being able to target different angles regardless of the variables in the installation. It sure does not maximize signal in any key target area where you might want the benefits of antenna gain.

<blockquote data-quote="Shockwave" data-source="post: 289116" data-attributes="member: 10882">You have to read his entire article on this topic, not just the parts someone else quoted from his links. Someone posted the original links on this site to Tom&#039;s site and I spent some time reading the whole thing. He does step back from the comments quoted here and basically contradicts himself saying that the 5/8 wave is not worse then the 1/4 wave but that there are examples of where the 1/4 can equal the 5/8 wave. The real point Tom is trying to make deals with &quot;reliability&quot; and how that relates to many variables with the 5/8 wave. This requires a good understanding of typical radiation patterns of the antennas in question. Dealling with how the groundplane radials and height above ground will impact the secondary lobes, their beamwidth, and the elevation angle of the primary lobe that&#039;s hopefully on the horizon.W8JI is saying that the 5/8 wave depends heavily on a good groundplane under the vertical and that its narrower beamwidth will be more affected by height above ground. The 1/4 wave also needs its groundplane under the vertical and its peak elevation angle will change with height too. The big difference is when you have the huge beamwidth of the 1/4 wave, you&#039;re literally sending out a radiation pattern that looks like a big ball in free space. That increases reliability by being able to target different angles regardless of the variables in the installation. It sure does not maximize signal in any key target area where you might want the benefits of antenna gain.</blockquote>

[QUOTE="Shockwave, post: 289116, member: 10882"] You have to read his entire article on this topic, not just the parts someone else quoted from his links. Someone posted the original links on this site to Tom's site and I spent some time reading the whole thing. He does step back from the comments quoted here and basically contradicts himself saying that the 5/8 wave is not worse then the 1/4 wave but that there are examples of where the 1/4 can equal the 5/8 wave. The real point Tom is trying to make deals with "reliability" and how that relates to many variables with the 5/8 wave. This requires a good understanding of typical radiation patterns of the antennas in question. Dealling with how the groundplane radials and height above ground will impact the secondary lobes, their beamwidth, and the elevation angle of the primary lobe that's hopefully on the horizon. W8JI is saying that the 5/8 wave depends heavily on a good groundplane under the vertical and that its narrower beamwidth will be more affected by height above ground. The 1/4 wave also needs its groundplane under the vertical and its peak elevation angle will change with height too. The big difference is when you have the huge beamwidth of the 1/4 wave, you're literally sending out a radiation pattern that looks like a big ball in free space. That increases reliability by being able to target different angles regardless of the variables in the installation. It sure does not maximize signal in any key target area where you might want the benefits of antenna gain. [/QUOTE]

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