Ham Radio Help Desk

I am preparing for the Virginia QSO Party and want to add an alternative 20 meter solution for my 43 foot vertical plus get better 15 and 10 meter coverage; I have been working plenty of 15 meter contacts with the 43 foot vertical so I know that band is open. Plus you never know if the sunspots might give us some 10 meter fun too

So…

I have been eagerly absorbing all there is to know about the hex beam style of HF antennas.

If you are the least bit interested in building or buying your own hex beam a must read web site is the G3TXQ study of the hex beam…
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Virginia hikers and hams supported the White Rock Cliffs (Station #6) of the first Annual Golden Packet Event.

Summarized, we were trying to set up APRS relay stations up and down the east coast to cover and service all points along the Appalachian Trail and surrounding areas. Some RF link analysis was performed and is available for viewing at http://www.packetradio.net/events/AT_Golden_Packet_Event/ using the remarkable Radio Mobile program and A LOT of SRTM elevation data.

Of the fourteen stations planned several points were accessible only by foot. The White Rock Cliffs station was no exception.
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While planning for a ham radio hike into the mountains to support the Appalachian Trail Golden Packet exercise, I asked my club members for ideas about a good portable 2 meter antenna.

One response included a link to this web page showcasing a collinear J-Pole antenna using two 5/8ths wave antenna elements.
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As my local club in northern Virginia prepares for the March Virginia QSO Party many questions are asked about how best to take full advantage of Near Vertical Incident Skywave (NVIS) communications so critical to maximizing contacts on HF within the state.

In particular one member has a magnificent full wave 160 meter loop up around 50 feet or so. He is contemplating using it for NVIS on 80 meters. He desires to lower it to about 15 feet to improve the NVIS characteristics.

It is true lowering a dipole will focus more energy straight up while reducing the energy towards the horizon. This is a tried and true technique on 80 and sometimes 40 meter NVIS and offers a potential added benefit of less sensitivity to far away thunderstorm noise. This is a method of diminishing returns; Lowering the antenna favors the sky more, but the overall gain is reduced. In other words, less signal is focused in a better NVIS favoring pattern.

Full wave loops are quite different as this EZNEC simulation suggests. Here is a simple four sided loop with 128 foot sides and fed near one corner – just like my friend’s 160 meter loop.
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We have looked at the 43 foot antenna available from DX Engineering and Zero Five alongside the BigIR product from SteppIR. In addition, the BigIR was simulated using the optional 80 meter coil.

Both antenna types approach the vertical HF antenna problem with unique solutions.
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As we continue our EZNEC simulation research for the 43 foot and BigIR antennas we finally are looking into the 80 meter band.
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Continuing our NEC Shootout between the 43 foot vertical available from DX Engineering or Zero Five and the adjustable height BigIR antenna available from SteppIR antennas we now analyze them in the 40 meter band.
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Continuing our NEC Shootout between the 43 foot vertical available from DX Engineering or Zero Five and the adjustable height BigIR antenna available from SteppIR antennas we now analyze them in the 20 meter band.
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Continuing our NEC Shootout between the 43 foot vertical available from DX Engineering or Zero Five and the adjustable height BigIR antenna available from SteppIR antennas we now analyze them in the 15 meter band.
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J-pole antennas are an interesting solution to the goal of more gain with a simple antenna. I won’t go into the specifics of what a J-pole is as there are plenty of sites on the Internet with good plans to help you build your own.

However, there seems to be much hype about j-poles that make some folks think they have some kind of magical antenna properties. Indeed many folks report staggering improvements over their previous antennas. Is all the hype warranted?
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