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The more you improve the RF ground the shorter the radiating element needs to be for a given frequency.

Performance increases won't really be noticeable to be honest although if you could put a RF current meter on your coax you'd notice a small drop in common mode RFI if you weren't using a choke.

You're right, ideally you should be using four 1/4 wave ones for an elevated antenna and in fact if you look at the new Sirio Tornado 27 it's basically a Sirio 827 but with four almost 1/4 wave long radials. You can use shorter ones if you increase their number, even as short as 1/8 wavelength because it's all about maximising current flow for the the H-plane, or magnetic field, which is at right angles to the E-plane, electrical one, and therefore horizontal on a vertical antenna. Because the maximum current is at the base of the antenna this is where it's the most important to have any radials and as you get further away from the base it becomes less important.

<blockquote data-quote="M0GVZ" data-source="post: 727159" data-attributes="member: 22312">The more you improve the RF ground the shorter the radiating element needs to be for a given frequency.Performance increases won&#039;t really be noticeable to be honest although if you could put a RF current meter on your coax you&#039;d notice a small drop in common mode RFI if you weren&#039;t using a choke.You&#039;re right, ideally you should be using four 1/4 wave ones for an elevated antenna and in fact if you look at the new Sirio Tornado 27 it&#039;s basically a Sirio 827 but with four almost 1/4 wave long radials.&nbsp; You can use shorter ones if you increase their number, even as short as 1/8 wavelength because it&#039;s all about maximising current flow for the the H-plane, or magnetic field, which is at right angles to the E-plane, electrical one, and therefore horizontal on a vertical antenna. Because the maximum current is at the base of the antenna this is where it&#039;s the most important to have any radials and as you get further away from the base it becomes less important.</blockquote>

[QUOTE="M0GVZ, post: 727159, member: 22312"] The more you improve the RF ground the shorter the radiating element needs to be for a given frequency. Performance increases won't really be noticeable to be honest although if you could put a RF current meter on your coax you'd notice a small drop in common mode RFI if you weren't using a choke. You're right, ideally you should be using four 1/4 wave ones for an elevated antenna and in fact if you look at the new Sirio Tornado 27 it's basically a Sirio 827 but with four almost 1/4 wave long radials. You can use shorter ones if you increase their number, even as short as 1/8 wavelength because it's all about maximising current flow for the the H-plane, or magnetic field, which is at right angles to the E-plane, electrical one, and therefore horizontal on a vertical antenna. Because the maximum current is at the base of the antenna this is where it's the most important to have any radials and as you get further away from the base it becomes less important. [/QUOTE]

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