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A friend who recently received his call is planning to setup an inverted-vee for 40/20m bands. Our take is the signal will take the path of least impedance into the correct length antenna wire.

Something like the image attached; it depicts two wires running right next to each other. The tab in the middle of the wire marks the end of the 20M, the other tab marks the end of the 40M length.

Inverted-Vee for 40/20

  • Can the antenna wires for both bands be fed at a common point by the coax?
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    $\begingroup$ Can you clarify the question and/or graphic? It's not clear what your trying to do. The graphic suggests a regular 2 wire dipole, but the text makes me thing you mean that you'll have 4 wires: 2 pairs, each cut to one of the desired bands. $\endgroup$ – Peter KB1AVL Oct 24 '13 at 14:59
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Yes, this works fine. It is often called a "fan dipole".

There are separate resonant dipoles for each band, all fed from a common point. The wires should be separated by a foot or more. If you have enough tie points at the ends, you can run them in slightly different directions.

The resonant dipole will have a low impedance, around 50 Ohms. The non-resonant one will have a higher impedance and will not accept much signal.

The antennas will interact with each other, so you may need to tune them to length iteratively. Most people start by adjusting the length of the longer antenna first.

The 40m antenna will also be close to resonance on 15m, so you can probably use it on that band with an antenna tuner.

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