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Beverage antenna consist of pair of transmission lines - one being the "antenna proper", the other ground. The antenna is being fed via open feed line ( approximately 450 Ohms ) - one side of line being "hot" and the other grounded. To achieve directivity , the antenna is also grounded , via 600 Ohm resistor at the far end.

The antenna is designed to be used on 14MHZ band and is little over 2 wavelength long.

The antenna works adequately as a receiving antenna. I can adjust my antenna coupler for maximum signal strength.

How do I adjust this , non - resonant antenna , to have MAXIMUM transfer of RF when used as transmitting antenna with 50Ohms "source" ?

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    $\begingroup$ Welcome to ham.stackexchange.com! $\endgroup$
    – rclocher3
    Jul 7, 2020 at 22:30
  • $\begingroup$ Hello Anne, what kind of "antenna coupler" do you mean? Can we assume an external antenna tuner? It might also help us if you could add a few more details. :-) $\endgroup$
    – Mike Waters ♦
    Aug 6, 2020 at 15:34

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Beverage antennas are extremely inefficient. For receive applications this is not much of a problem, but for transmitting it's a big problem.

As such, trying to match a transmitter to such an antenna is a futile exercise. At best, what you would achieve would not be much better than a dummy load. Most of your transmitter power will just make warm soil. You would get much better results from nearly any other antenna, even if it is just a mobile whip with a terrible ground plane.

That said, matching a transmitter to a Beverage antenna is no different than matching a transmitter to any other antenna. You could use an antenna tuner or make a fixed matching network from capacitors, inductors, transformers, and/or transmission lines.

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  • $\begingroup$ Last paragraph is fine, but any Beverage is better than a dummy load. $\endgroup$
    – Mike Waters ♦
    Aug 6, 2020 at 15:21
  • $\begingroup$ Indeed, that's what "not much better" means. $\endgroup$
    – Phil Frost - W8II
    Aug 6, 2020 at 17:37
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A non-resonant Beverage antenna shouldn't need a tunable matching network for either transmitting or receiving (but as Phil nicely stated, you certainly can use one). All you really need is a proper broadband matching transformer, 9:1 for a 50 ohm feedline and 6.25:1 for 75 ohm. It is better to connect the Beverage directly to it and then run coax between it and your station.

Phil is correct about the losses (my Beverages have about 10 dB of loss) and that it mostly futile to transmit on them. However, myself and other happy Beverage antenna users have successfully transmitted on them. Among other things, it's a matter of how the gain and takeoff angle of a Beverage compares with another antenna over a given DX path and band conditions.

For example, one afternoon last year I compared my low N-S 75m dipole with my 580' NE Beverage. I was in QSO with a couple of hams in New York State from my QTH in SW Missouri. I had to transmit on my Beverage because they could barely hear me on my dipole. On another occasion, I had a significant signal into Europe transmitting on this same Beverage compared to another antenna.

Usually, 40 or 30 meters is about the highest band that they are useful on, but there have been exceptions. W8JI told me that on occasion, his 580' Beverages heard a 20m DX signal that his high Yagi could not.

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