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The problem is the fact that the antenna isn't going to be a tuned antenna.

Lets take a look at what happens to said efficiency when SWR goes up, this is with 220 feet of LMR-400 at 27.2 MHz. Here we have SWR in the first column, dB loss in the second column, and percent of transmitted power absorbed by the antenna in the third column.

1:1 SWR 1.397 dB 72.495%
2:1 SWR 1.647 dB 68.437%
3:1 SWR 2.035 dB 62.596%
4:1 SWR 2.424 dB 57.224%
5:1 SWR 2.794 dB 52.55%

As the SWR of the as specified "non-resonant" antenna is potentially even higher, the losses with LMR-400 could get even higher than this, and by more than I think many people realize. Further, the hit to the RG-8/U that you mentioned would be even bigger then what is shown here. Also, a 5/8 wavelength vertical without a matching circuit will have an SWR of around 8:1 (give or take depending on specific design), which would be even worse than the above numbers.

Coax is great as long as you have a matched antenna on the other end, but it quickly falls apart when feeding into unknown impedance loads like the OP is doing.

The DB

<blockquote data-quote="The DB" data-source="post: 849256" data-attributes="member: 21346">The problem is the fact that the antenna isn&#039;t going to be a tuned antenna.Lets take a look at what happens to said efficiency when SWR goes up, this is with 220 feet of LMR-400 at 27.2 MHz.&nbsp; Here we have SWR in the first column, dB loss in the second column, and percent of transmitted power absorbed by the antenna in the third column.<table style='width: 100%'><tr><td>1:1 SWR</td><td>1.397 dB</td><td>72.495%</td></tr><tr><td>2:1 SWR</td><td>1.647 dB</td><td>68.437%</td></tr><tr><td>3:1 SWR</td><td>2.035 dB</td><td>62.596%</td></tr><tr><td>4:1 SWR</td><td>2.424 dB</td><td>57.224%</td></tr><tr><td>5:1 SWR</td><td>2.794 dB</td><td>52.55%</td></tr></table>As the SWR of the as specified &quot;non-resonant&quot; antenna is potentially even higher, the losses with LMR-400 could get even higher than this, and by more than I think many people realize.&nbsp; Further, the hit to the RG-8/U that you mentioned would be even bigger then what is shown here.&nbsp; Also, a 5/8 wavelength vertical without a matching circuit will have an SWR of around 8:1 (give or take depending on specific design), which would be even worse than the above numbers.Coax is great as long as you have a matched antenna on the other end, but it quickly falls apart when feeding into unknown impedance loads like the OP is doing.The DB</blockquote>

[QUOTE="The DB, post: 849256, member: 21346"] The problem is the fact that the antenna isn't going to be a tuned antenna. Lets take a look at what happens to said efficiency when SWR goes up, this is with 220 feet of LMR-400 at 27.2 MHz. Here we have SWR in the first column, dB loss in the second column, and percent of transmitted power absorbed by the antenna in the third column. [TABLE] [TR] [TD]1:1 SWR[/TD] [TD]1.397 dB[/TD] [TD]72.495%[/TD] [/TR] [TR] [TD]2:1 SWR[/TD] [TD]1.647 dB[/TD] [TD]68.437%[/TD] [/TR] [TR] [TD]3:1 SWR[/TD] [TD]2.035 dB[/TD] [TD]62.596%[/TD] [/TR] [TR] [TD]4:1 SWR[/TD] [TD]2.424 dB[/TD] [TD]57.224%[/TD] [/TR] [TR] [TD]5:1 SWR[/TD] [TD]2.794 dB[/TD] [TD]52.55%[/TD] [/TR] [/TABLE] As the SWR of the as specified "non-resonant" antenna is potentially even higher, the losses with LMR-400 could get even higher than this, and by more than I think many people realize. Further, the hit to the RG-8/U that you mentioned would be even bigger then what is shown here. Also, a 5/8 wavelength vertical without a matching circuit will have an SWR of around 8:1 (give or take depending on specific design), which would be even worse than the above numbers. Coax is great as long as you have a matched antenna on the other end, but it quickly falls apart when feeding into unknown impedance loads like the OP is doing. The DB [/QUOTE]

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1:1 SWR	1.397 dB	72.495%
2:1 SWR	1.647 dB	68.437%
3:1 SWR	2.035 dB	62.596%
4:1 SWR	2.424 dB	57.224%
5:1 SWR	2.794 dB	52.55%