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i wrote:

"moving the radials upward in close proximity to to radiating element compresses the electric and magnetic charge while increasing the capacitance between the radials and the vertical element. this creates additional loss resistance. it drives down input resistance (now you need the gamma match) while also driving the frequency down the band, now requiring the lengthening of the vertical element by +or- 5.5" to bring it back up into the band and with the additional loss the swr bandwidth is wider than it should be. it is not well known that as loss resistance increases in an antenna system that the bandwidth will be widened but for all the wrong reasons. claims of ever increasing swr bandwidths mean more Rloss / loss resistance (bad) and less Rrad / radiation resistance. (bad) altogether it all adds up to reduced antenna radiation efficiency."

correction:

moving the radials upward in close proximity to to radiating element compresses the electric and magnetic charge while increasing the capacitance between the radials and the vertical element. this creates additional loss resistance. it drives down input resistance (now you need the gamma match) while also driving the frequency up the band, now requiring the lengthening of the vertical element by +or- 5.5" to bring it back down into the band and with the additional loss the swr bandwidth is wider than it should be. it is not well known that as loss resistance increases in an antenna system that the bandwidth will be widened but for all the wrong reasons. claims of ever increasing swr bandwidths mean more Rloss / loss resistance (bad) and less Rrad / radiation resistance. (bad) it all adds up to reduced antenna radiation efficiency and directivity..

<blockquote data-quote="freecell" data-source="post: 765662" data-attributes="member: 30">i wrote:&quot;moving the radials upward in close proximity to to radiating element compresses the electric and magnetic charge while increasing the capacitance between the radials and the vertical element. this creates additional loss resistance. it drives down input resistance (now you need the gamma match) while also driving the frequency down the band, now requiring the lengthening of the vertical element by +or- 5.5&quot; to bring it back up into the band and with the additional loss the swr bandwidth is wider than it should be. it is not well known that as loss resistance increases in an antenna system that the bandwidth will be widened but for all the wrong reasons. claims of ever increasing swr bandwidths mean more Rloss / loss resistance (bad) and less Rrad / radiation resistance. (bad) altogether it all&nbsp; adds up to reduced antenna radiation efficiency.&quot;correction:moving the radials upward in close proximity to to radiating element compresses the electric and magnetic charge while increasing the capacitance between the radials and the vertical element. this creates additional loss resistance. it drives down input resistance (now you need the gamma match) while also driving the frequency up the band, now requiring the lengthening of the vertical element by +or- 5.5&quot; to bring it back down into the band and with the additional loss the swr bandwidth is wider than it should be. it is not well known that as loss resistance increases in an antenna system that the bandwidth will be widened but for all the wrong reasons. claims of ever increasing swr bandwidths mean more Rloss / loss resistance (bad) and less Rrad / radiation resistance. (bad) it all adds up to reduced antenna radiation efficiency and directivity..</blockquote>

[QUOTE="freecell, post: 765662, member: 30"] i wrote: "moving the radials upward in close proximity to to radiating element compresses the electric and magnetic charge while increasing the capacitance between the radials and the vertical element. this creates additional loss resistance. it drives down input resistance (now you need the gamma match) while also driving the frequency down the band, now requiring the lengthening of the vertical element by +or- 5.5" to bring it back up into the band and with the additional loss the swr bandwidth is wider than it should be. it is not well known that as loss resistance increases in an antenna system that the bandwidth will be widened but for all the wrong reasons. claims of ever increasing swr bandwidths mean more Rloss / loss resistance (bad) and less Rrad / radiation resistance. (bad) altogether it all adds up to reduced antenna radiation efficiency." correction: moving the radials upward in close proximity to to radiating element compresses the electric and magnetic charge while increasing the capacitance between the radials and the vertical element. this creates additional loss resistance. it drives down input resistance (now you need the gamma match) while also driving the frequency up the band, now requiring the lengthening of the vertical element by +or- 5.5" to bring it back down into the band and with the additional loss the swr bandwidth is wider than it should be. it is not well known that as loss resistance increases in an antenna system that the bandwidth will be widened but for all the wrong reasons. claims of ever increasing swr bandwidths mean more Rloss / loss resistance (bad) and less Rrad / radiation resistance. (bad) it all adds up to reduced antenna radiation efficiency and directivity.. [/QUOTE]

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