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sp5it,
You're sort of right with a few qualifiers added in. One of those qualifiers is height above ground with either of those two types of dipoles. Below a 1/2 wave length, neither is very directional at all. As that 1/2 wave above ground is approached, things start to get sort of bi-directional. You've got as much directionality as you'll get when you get to about 1 wave length above ground (with either of those two types of dipoles).
Another qualifier is the angle between the legs of that inverted 'V'. If it's greater than about 120 degrees, then you can figure on it having a directional pattern about like a 'flat-top' dipole. At less than 120 degrees things start to 'spread out', less directionality, till you get to around 90 degrees between the legs. At that point, quit, less than 90 degrees isn't good for anything. Actually, an inverted 'V' is a dipole with an angle of 90 degrees between the legs. It does have some benefits, but nothing as optimistic as is usually claimed. It also has a few 'bad' characteristics. As in the input impedance isn't going to be near 50 ohms, and it get's a bit ticklish for matching to 50 ohm coax. Most of the "inverted 'V'" antennas you see are really more of a 'drooping' dipole, closer to around 120 degrees between the legs. And as already said, that 'droop' contributes to impedance matching while still keeping a resonant length.
- 'Doc

<blockquote data-quote="W5LZ" data-source="post: 221369" data-attributes="member: 129">sp5it,You&#039;re sort of right with a few qualifiers added in.&nbsp; One of those qualifiers is height above ground with either of those two types of dipoles.&nbsp; Below a 1/2 wave length, neither is very directional at all.&nbsp; As that 1/2 wave above ground is approached, things start to get sort of bi-directional.&nbsp; You&#039;ve got as much directionality as you&#039;ll get when you get to about 1 wave length above ground (with either of those two types of dipoles).Another qualifier is the angle between the legs of that inverted &#039;V&#039;.&nbsp; If it&#039;s greater than about 120 degrees, then you can figure on it having a directional pattern about like a &#039;flat-top&#039; dipole.&nbsp; At less than 120 degrees things start to &#039;spread out&#039;, less directionality, till you get to around 90 degrees between the legs.&nbsp; At that point, quit, less than 90 degrees isn&#039;t good for anything.&nbsp; Actually, an inverted &#039;V&#039; is a dipole with an angle of 90 degrees between the legs.&nbsp; It does have some benefits, but nothing as optimistic as is usually claimed.&nbsp; It also has a few &#039;bad&#039; characteristics.&nbsp; As in the input impedance isn&#039;t going to be near 50 ohms, and it get&#039;s a bit ticklish for matching to 50 ohm coax.&nbsp; Most of the &quot;inverted &#039;V&#039;&quot; antennas you see are really more of a &#039;drooping&#039; dipole, closer to around 120 degrees between the legs.&nbsp; And as already said, that &#039;droop&#039; contributes to impedance matching while still keeping a resonant length.&nbsp;- &#039;Doc</blockquote>

[QUOTE="W5LZ, post: 221369, member: 129"] sp5it, You're sort of right with a few qualifiers added in. One of those qualifiers is height above ground with either of those two types of dipoles. Below a 1/2 wave length, neither is very directional at all. As that 1/2 wave above ground is approached, things start to get sort of bi-directional. You've got as much directionality as you'll get when you get to about 1 wave length above ground (with either of those two types of dipoles). Another qualifier is the angle between the legs of that inverted 'V'. If it's greater than about 120 degrees, then you can figure on it having a directional pattern about like a 'flat-top' dipole. At less than 120 degrees things start to 'spread out', less directionality, till you get to around 90 degrees between the legs. At that point, quit, less than 90 degrees isn't good for anything. Actually, an inverted 'V' is a dipole with an angle of 90 degrees between the legs. It does have some benefits, but nothing as optimistic as is usually claimed. It also has a few 'bad' characteristics. As in the input impedance isn't going to be near 50 ohms, and it get's a bit ticklish for matching to 50 ohm coax. Most of the "inverted 'V'" antennas you see are really more of a 'drooping' dipole, closer to around 120 degrees between the legs. And as already said, that 'droop' contributes to impedance matching while still keeping a resonant length. - 'Doc [/QUOTE]

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