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Phil501,

For an inverted 'V' configuration, the length given is a half wave length, and twice that length would be a full wave length. The length of a ~resonant~ half wave length at a particular frequency changes due to several things, diameter of the conductor, the physical relationship between the 'halves' of a dipole, and height above ground. With an SWR of 1.4<img src=http://users.joplin.com/dutch64804/posticon1.gif ALT=":1"> it sounds like yours is about as 'close' as it gets.

An inverted 'V' antenna is essentially an omnidirectional antenna and horizontally polarized. They typically have a higher 'take off' angle than a vertical antenna but the difference isn't all that important, certainly not enough to worry about when looking for 'DX'.

The 'quieter than an Imax' is because of the antenna's polarization. Vertically polarized antennas 'hear' more noise because most man- made noise is vertically polarized. So, in general, a horizontally polarized antenna tends to be 'quieter'. The difference in noise usually isn't all ~that~ great, but there is a difference.

A balun usually isn't necessary with an inverted 'V', the impedance is usually very close to 50 ohms so the impedance matching ability of a balun isn't needed, and the balanced-to-unbalanced thingy just isn't that big'a deal at HF. [About the only affect of using a balun at HF is the shape of the radiation pattern, it'll be slightly 'skewed' at HF not using a balun. Still, not a big deal at HF.]

There's nothing wrong with a 1.4<img src=http://users.joplin.com/dutch64804/posticon1.gif ALT=":1"> SWR but if you want to play with reducing it some, try changing the angle between the legs of the antenna. Shouldn't take much to make a change in the SWR. That 'angle of the dangle' works with any dipole to change the input impedance, by the way, not just an inverted 'V'.

- 'Doc

PS - For the 'purist', or to be really picky, an inverted 'V' antenna is one that has an angle of 90 degrees between the legs. At angles greater than 90 degrees the antenna is called a 'drooping' dipole. At angles less than 90 degrees, it's called a 'dummy load'...

<blockquote data-quote="W5LZ" data-source="post: 14555" data-attributes="member: 129">Phil501,For an inverted &#039;V&#039; configuration, the length given is a half wave length, and twice that length would be a full wave length.&nbsp; The length of a ~resonant~ half wave length at a particular frequency changes due to several things, diameter of the conductor, the physical relationship between the &#039;halves&#039; of a dipole, and height above ground.&nbsp; With an SWR of 1.4&lt;img src=http://users.joplin.com/dutch64804/posticon1.gif ALT=&quot;:1&quot;&gt;&nbsp; it sounds like yours is about as &#039;close&#039; as it gets.An inverted &#039;V&#039; antenna is essentially an omnidirectional antenna and horizontally polarized.&nbsp; They typically have a higher &#039;take off&#039; angle than a vertical antenna but the difference isn&#039;t all that important, certainly not enough to worry about when looking for &#039;DX&#039;.The &#039;quieter than an Imax&#039; is because of the antenna&#039;s polarization.&nbsp; Vertically polarized antennas &#039;hear&#039; more noise because most man- made noise is vertically polarized.&nbsp; So, in general, a horizontally polarized antenna tends to be &#039;quieter&#039;.&nbsp; The difference in noise usually isn&#039;t all ~that~ great, but there is a difference.A balun usually isn&#039;t necessary with an inverted &#039;V&#039;, the impedance is usually very close to 50 ohms so the impedance matching ability of a balun isn&#039;t needed, and the balanced-to-unbalanced thingy just isn&#039;t that big&#039;a deal at HF.&nbsp; [About the only affect of using a balun at HF is the shape of the radiation pattern, it&#039;ll be slightly &#039;skewed&#039; at HF not using a balun.&nbsp; Still, not a big deal at HF.]There&#039;s nothing wrong with a 1.4&lt;img src=http://users.joplin.com/dutch64804/posticon1.gif ALT=&quot;:1&quot;&gt;&nbsp; SWR but if you want to play with reducing it some, try changing the angle between the legs of the antenna.&nbsp; Shouldn&#039;t take much to make a change in the SWR.&nbsp; That &#039;angle of the dangle&#039; works with any dipole to change the input impedance, by the way, not just an inverted &#039;V&#039;.&nbsp;- &#039;DocPS - For the &#039;purist&#039;, or to be really picky, an inverted &#039;V&#039; antenna is one that has an angle of 90 degrees between the legs.&nbsp; At angles greater than 90 degrees the antenna is called a &#039;drooping&#039; dipole.&nbsp; At angles less than 90 degrees, it&#039;s called a &#039;dummy load&#039;...&nbsp;&lt;/p&gt;</blockquote>

[QUOTE="W5LZ, post: 14555, member: 129"] Phil501, For an inverted 'V' configuration, the length given is a half wave length, and twice that length would be a full wave length. The length of a ~resonant~ half wave length at a particular frequency changes due to several things, diameter of the conductor, the physical relationship between the 'halves' of a dipole, and height above ground. With an SWR of 1.4<img src=http://users.joplin.com/dutch64804/posticon1.gif ALT=":1"> it sounds like yours is about as 'close' as it gets. An inverted 'V' antenna is essentially an omnidirectional antenna and horizontally polarized. They typically have a higher 'take off' angle than a vertical antenna but the difference isn't all that important, certainly not enough to worry about when looking for 'DX'. The 'quieter than an Imax' is because of the antenna's polarization. Vertically polarized antennas 'hear' more noise because most man- made noise is vertically polarized. So, in general, a horizontally polarized antenna tends to be 'quieter'. The difference in noise usually isn't all ~that~ great, but there is a difference. A balun usually isn't necessary with an inverted 'V', the impedance is usually very close to 50 ohms so the impedance matching ability of a balun isn't needed, and the balanced-to-unbalanced thingy just isn't that big'a deal at HF. [About the only affect of using a balun at HF is the shape of the radiation pattern, it'll be slightly 'skewed' at HF not using a balun. Still, not a big deal at HF.] There's nothing wrong with a 1.4<img src=http://users.joplin.com/dutch64804/posticon1.gif ALT=":1"> SWR but if you want to play with reducing it some, try changing the angle between the legs of the antenna. Shouldn't take much to make a change in the SWR. That 'angle of the dangle' works with any dipole to change the input impedance, by the way, not just an inverted 'V'. - 'Doc PS - For the 'purist', or to be really picky, an inverted 'V' antenna is one that has an angle of 90 degrees between the legs. At angles greater than 90 degrees the antenna is called a 'drooping' dipole. At angles less than 90 degrees, it's called a 'dummy load'... [i][/i] [/QUOTE]

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