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Interesting.

Do you have the usual DE/Reflector, or are you using a director (I've used both, they work the same)? What are the dimensions of the loops and what's the spacing. The feedpoint impedance of a quad (and a 2 element yagi for that matter) can vary quite a bit (40 to 125 ohms in the case of the quad) depending on the spacing.

What's your source for the 1/12 section? I don't see how that would provide much of an impedance transformation but maybe I'm missing something. If your VSWR was that high with a 1/4 wave 75 ohm Q section it looks like there may have been some other issues. These antennas are not usually hard to match to 50 ohms. On your 1/4 wave section, was the coax poly or foam dielectric, and how long was it?

Sorry for all the questions, I'm just trying to figure out why that didn't work in this case. I've used that matching method a bunch of times from 7 to 29 MHz and have never had a problem with it.

Thanks,

Rick

<blockquote data-quote="RickC." data-source="post: 141138" data-attributes="member: 9297">Interesting.&nbsp;Do you have the usual DE/Reflector, or are you using a director (I&#039;ve used both, they work the same)?&nbsp; What are the dimensions of the loops and what&#039;s the spacing.&nbsp; The feedpoint impedance of a quad (and a 2 element yagi for that matter) can vary quite a bit (40 to 125 ohms in the case of the quad) depending on the spacing.&nbsp; What&#039;s your source for the 1/12 section?&nbsp; I don&#039;t see how that would provide much of an impedance transformation but maybe I&#039;m missing something.&nbsp; If your VSWR was that high with a 1/4 wave 75 ohm Q section it looks like there may have been some other issues.&nbsp; These antennas are not usually hard to match to 50 ohms.&nbsp; On your 1/4 wave section, was the coax poly or foam dielectric, and how long was it?Sorry for all the questions, I&#039;m just trying to figure out why that didn&#039;t work in this case.&nbsp; I&#039;ve used that matching method a bunch of times from 7 to 29 MHz and have never had a problem with it.Thanks,Rick</blockquote>

[QUOTE="RickC., post: 141138, member: 9297"] Interesting. Do you have the usual DE/Reflector, or are you using a director (I've used both, they work the same)? What are the dimensions of the loops and what's the spacing. The feedpoint impedance of a quad (and a 2 element yagi for that matter) can vary quite a bit (40 to 125 ohms in the case of the quad) depending on the spacing. What's your source for the 1/12 section? I don't see how that would provide much of an impedance transformation but maybe I'm missing something. If your VSWR was that high with a 1/4 wave 75 ohm Q section it looks like there may have been some other issues. These antennas are not usually hard to match to 50 ohms. On your 1/4 wave section, was the coax poly or foam dielectric, and how long was it? Sorry for all the questions, I'm just trying to figure out why that didn't work in this case. I've used that matching method a bunch of times from 7 to 29 MHz and have never had a problem with it. Thanks, Rick [/QUOTE]

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