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I don't know what a dummy load has to do with anything here. A perfect dummy load exhibits infinite radiation resistance. A perfect antenna/matching system exhibits radiation resistance equal to the source impedance feeding it.

Given a good match means whatever antenna under test is working to it's capability. If you see two 5/8ths physical length antenna both with low SWR showing 6 dB difference something is way off with the test setup. 6dB is quite a difference.

Yes, you are missing something with the test. Maybe try more distance and hook up several of those mighty dipoles to prove your method.

Seasoned VHF operators will all tell you reception can vary markedly by simply moving a few feet.

Try a 100 watt carrier for 5 minutes straight into any antenna suspected of dielectric losses in it's construction. Sniff, record results.

<blockquote data-quote="HiDef" data-source="post: 152181" data-attributes="member: 7734">I don&#039;t know what a dummy load has to do with anything here. A perfect dummy load exhibits infinite radiation resistance. A perfect antenna/matching system exhibits radiation resistance equal to the source impedance feeding it. Given a good match means whatever antenna under test is working to it&#039;s capability. If you see two 5/8ths physical length antenna both with low SWR showing 6 dB difference something is way off with the test setup. 6dB is quite a difference. Yes, you are missing something with the test. Maybe try more distance and hook up several of those mighty dipoles to prove your method. Seasoned VHF operators will all tell you reception can vary markedly by simply moving a few feet. Try a 100 watt carrier for 5 minutes straight into any antenna suspected of dielectric losses in it&#039;s construction. Sniff, record results.</blockquote>

[QUOTE="HiDef, post: 152181, member: 7734"] I don't know what a dummy load has to do with anything here. A perfect dummy load exhibits infinite radiation resistance. A perfect antenna/matching system exhibits radiation resistance equal to the source impedance feeding it. Given a good match means whatever antenna under test is working to it's capability. If you see two 5/8ths physical length antenna both with low SWR showing 6 dB difference something is way off with the test setup. 6dB is quite a difference. Yes, you are missing something with the test. Maybe try more distance and hook up several of those mighty dipoles to prove your method. Seasoned VHF operators will all tell you reception can vary markedly by simply moving a few feet. Try a 100 watt carrier for 5 minutes straight into any antenna suspected of dielectric losses in it's construction. Sniff, record results. [/QUOTE]

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