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15 portable HF wire antennas to try
Here is a selection of portable HF wire antennas that I've had good results with. None are avery complex and all can be erected at a portable site in a few minutes. Videos below describe
and demonstrate them in action. Gather the following main items to start experimenting:
* At least one lightweight portable mast, such as a telescoping squid pole. 9 metres is a good all-round length. 5 metres poles are small and light while 12 metre poles are more robust.
More at Various antenna masts demonstrated.
* Velcro strap to allow the mast to be securely tied to a fence or gate. And/or a sand spike.
* Lots of light insulated wire. Can be thin stranded plastic covered type for temporary portable use. A 100 metre reel is good.
* Pieces of chopping board to make antenna insulators.
* An antenna coupler. L-matches are good for end-fed or coax fed antennas while balanced types are good for balanced feedline antennas. Ideas at
Antenna couplers galore.
Link dipole
It's easy to make a half wave dipole but hard to make a portable antenna that's appreciably better than one. A dipole's main limitation (if fed with coax) is that it (generally)
only works on a single band. To easily overcome this you can make a link dipole. This is a half wave dipole with the element split so that you can lower the centre and change bands by clipping
and unclipping part of the antenna. You get no-compromise dipole performance on all design bands. It works well for casual portable operation provided you don't need to change bands instantly.
---3m---o--2m--o-----5m-----O-----5m-----o--2m--o---3m---
o is a gap which is bridged with an alligator clip for a lower frequency band. You may need to change the dimensions slightly. To do so start with optimising the length of the inner portion (for 14 MHz) with the clips for the other sections open. Then optimise for 10 MHz, with the inner two clips closed circuit. Finally optimise for 7 MHz with all clips bridged. The video below doesn't show the antenna much but it does demonstrate its performance during the SSB section of the ARRL DX Contest.
Tuned feeder dipoleThis is a half wave dipole for 7 MHz (ie 10 m wire either side of the feedline) but fed with ladder feedline. In conjunction with a balanced antenna coupler like that described it allows efficient operation on HF frequencies from 5 MHz to 28 MHz. Open wire feedline and the larger coupler adds weight but unlike the link dipole above you get faster band switching from the transceiver end by adjusting the coupler.
End-fed half wavelength wireAn end-fed half wavelength wire and small coupler is my default portable antenna if I just want to take the minimum. Wire length isn't that critical (approximately 22m radiating element plus a small counterpoise of 2 or 3 metres) for coverage of most HF bands 7 MHz and up with a small coupler. I typically support it on a telescoping 9m pole and configure the wire so it looks like an inverted-vee (with the transceiver near one end). Here's a video of a typical outing.
Triband end-fed wire antennaHere's a smaller version of the end-fed half wavelength wire antenna ideal for tight spots. It uses a loading coil to reduce length by about 40%. Also offered is the convenience of switching between popular bands without twiddling an antenna coupler.
TLI verticalThis is a great one for the antenna experimenter, especially if you're operating over salt water. It's three antennas in one; T L and I shaped. I switched between them to do comparisons. Which one is consistently better? Watch the first video below and find out!
A vertical dipole on 14 MHzA vertical coax fed dipole can be all you need if operation on a single band only is required. If over or near salt water it's a great no-frills DX antenna. Videos show DX being worked from Australia.
14 MHz half wavelength wire vertical (10m long)A half wavelength wire vertical can be coiled up small, with a 9 metre telescoping pole taking up the most room. Other items needed include a sand spike and an L-match antenna coupler. The videos shows it being used on a beach or pier. It's a half wavelength on 14 MHz but the antenna coupler allows operation on other bands without needing to trim the antenna wire. Of course it then ceases to be a half wavelength on these other bands; on 7 MHz it's a 1/4 wavelength, 10 MHz 1/3 wavelength, 18 MHz a 5/8 wavelength and 21 MHz a 3/4 wavelength.
14 & 18 MHz vertical with tuned counterpoiseRadials can be a pain. Especially in public places where people and dogs can trip over them. Something that I've found works well is a tuned counterpoise. More in the video below.
Using a sand spike (for a 21 MHz on the beach vertical)Simple is often best and this 21 MHz vertical is no exception. Installed right on the sand it's achieved great results. The only problem is how to support it with no trees or fences around. The solution is a sand spike. Either buy one or make your own. It needn't go very deep if you're just using a lightweight pole and wire vertical antenna.
Vertically polarised delta loop for 20 metresIf you want good performance on a single band and are near salt water it's hard to go past a vertically polarised single element delta loop. These videos show what's involved. And as you'll hear a delta loop can give results some choose not to believe!
Multiband delta loopThis loop is a little like the above but uses slotted twin feedline and a balanced antenna coupler. That allows it to operate efficiently on several bands; typically from about 0.7 to 1.5 times the design frequency. Better results would have been possible if the antenna was direclty over the water shown in the video.
Vertically polarised rectangular loop for 40, 30 & 20 metres
Another good antenna for good DX performance near salt water is the vertically polarised rectangular loop. Like the delta loop it's a full wavelength perimeter on its design
frequency. But unlike the delta loop it needs two supports. These don't need to be as tall as the single support for the delta loop. I could have made the loop a square
(quad) loop but didn't. Instead I went for a rectangle that is 2/3 wavelength wide and 1/3 wavelength high. Why? The squashed shape makes it even easier to erect with
low supports. This is an advantage if your poles are only 8 or 9 metres tall, such as the popular fishing poles portable QRPers use.
The first video is a full wavelength 20 metre perimeter loop on 14 MHz. I try it with QRP WSPR with results from around the world. The second video is a larger loop
30 metres in perimeter. It's multiband due to its use of twin slotted feedline and a balanced antenna coupler. I try it on 7, 10 and 14 MHz, alternating between
horizontal and vertical polarisation by moving the feedpoint. As you might expect, and as the theory books tell us, vertical is superior for longer distances.
Half square antennasAnother great low-angle salt water DX performer is the half square. It's a very simple bidirectional gain antenna. You just need one wavelength of wire, bent into a shallow inverted U, and two support poles a bit taller than a quarter wavelength each. Gain is broadside to the wire so consider its orientation relative to the DX you wish to work. The half square is a great choice if you don't have very tall masts. The videos demonstrate versions for 30 and 20 metres with the last one showing its directionality as I move the wire around when someone is talking.
Bobtail curtainTried a half-square and liked it? Want even more low-angle DX gain concentrated in narrower bidirectional lobes? Don't have very tall poles but have lots of horizontal space? If all these apply consider the Bobtail curtain. Look at a great circle map for the DX you wish to work before you go out portable and pack a compass. That will help you orient it for the right direction (bidirectional broadside pattern) for your favoured DX. Learn all about it here.
End-fed full wavelength inverted vee
So you were intrigued by the half-square but can only take one pole with you? Or there's only one tall tree that you can throw a line up in to?
Want something that doubles as an end-fed half wavelength on 7 MHz? The good news is that you can get half-square type DX performance with just
one support pole if you set the antenna up as an end-fed full wavelength inverted vee. Grab 20 - 22 metres of wire, an 8 or 9 metre pole,
an L-match antenna coupler and a small counterpoise and you too can have a few dB of bidirectional low angle gain ideal for working 14 MHz DX. Even better
is that this antenna will work as an end-fed half wavelength wire on 7 MHz (roughly omnidirectional and good for closer in contacts) and an end-fed
2/3 wavelength wire on 10 MHz (again with a little gain good for DX). Overall this is my most used portable antenna due to its speed of erection and performance.
More in the videos below.
If you make the above 1 wavelength wire asymmetrical with an off-centre support point and the part nearest the transceiver vertical
you can get a null in a certain direction. This doesn't do much to the gain but gives a null off the rear. This is good if you are operating
in an urbanised coastal area where you want to null out interference from buildings on the land. That's featured in the last two videos.
Operating with a vertical MoxonA Moxon is basically a small two element beam with the outer portions of the elements bent in towards themselves. This is a particular benefit for vertical antennas as the support poles do not need to be as tall. A Moxon takes longer to erect than some of the simpler antennas described. You may need to use two masts. Because elements are critically coupled careful adjustment may be required for best performance. Nevertheless they can give good performance and are a popular choice amongst space-saving DXers.
A 21 MHz vertical beam for the beachThe above Moxon is a bit unwieldy for short-term portable operating. Wire elements can flap around in the wind and the critical coupling means that performance can vary. Is there a better way more suited to the casual portable operator? In the first two videos I start with an off-centre vertical capable of multiband operation with a simple antenna coupling unit. These show that driven element length isn't very critical provided you've sorted out the impedance matching. Then in the third video I add a parasitic element (whose length and position is critical) for some gain and directivity on 21 MHz. On a gain per dollar basis this is hard to beat especially for single band beachside operating.
A bisquare for 28 MHzEven though it's for 28 MHz it's still a monster. The bi-square looks like a quad loop except instead of one wavelength of wire it's two wavelengths circumference. The other difference is that it's open at the top so is not a true loop. This video demonstrates portable operation with it supported by a 9 metre telescoping pole.
'Any old bit of metal'Sometimes you're desperate to get on air. You leave that all-important antenna wire at home. Or you feel like doing things the 'hard way'. In the spirit of improvisation I walk along my local beach to see what can be loaded up as an antenna (with varying results).
Kite-supported wire antennasA kite is the best way to get your wire up really high and get a 'big gun' signal on lower bands like 160 metres. Read all about it at Experiences with kite-supported wire antennas.
5 metre long wire antenna for 7 - 50 MHz pedestrian mobileAll wire antennas described above have been for portable operating. But wire antennas can also be used on the move if supported by a pole. A wire length of 5 metres forms a quarter wavelength on 14 MHz and a half wavelength on 28 MHz. A centre loading coil can make it tolerably good on 7 MHz. These and other bands can be covered with a wire of this length with a small antenna coupler. For further details see Wadetenna for pedestrian mobile HF.
Making sense of it all
If you've got down this far you'll see there's numerous possibilities for wire antennas. Key choices include (i) single or multi band, (ii) local or DX bias in performance
and (iii) tolerable weight and size if carrying.
Below is a quick guide listing popular wire antennas and their pros and cons. It's over-simplified and may not apply for all circumstances. For instance while vertical
antennas are favoured for DX they are also the antenna of choice for local groundwave coverage on bands like 160 metres. Sometimes
the same antenna can be listed twice, depending on the operating frequency. For example a wire vertical 10 metres long is a half wavelength on 14 MHz but only a quarter wavelength
on 7 MHz. Also radiation patterns can vary with antennas used on multiple bands and results in some directions may be appreciably worse or better than a reference dipole.
Items were chosen for likely usefulness and a satisfaction rating of 4/5 or better.
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Books by VK3YE
Ham Radio Get Started (USA)Australian Ham Radio Handbook (Aust) More Hand-carried QRP Antennas 99 things you can do with Amateur Radio Getting back into Amateur Radio Illustrated International Ham Radio Dictionary Make your Passion Pay (ebook writing)
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