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Equipment for portable HF operations

W4GS 3-band used during field days.

A 3-band beam used during a Field Days activity.

Selecting a portable HF antenna (II)

What antennas are today available on the place for portable operations ? By definition a portable station is a station located at another location that the base one but not set up as a fixed station (thus /P, not /A). Optionally this second station is subject to move from time to time, but not as regularly or as fast as a mobile one. This location has not only to be located a few km away from the QTH but can be a spot selected for the holidays, sometimes abroad and that you can also sometimes only reach by boat or by plane.

So that means than the antenna used for a portable operation must be light but it can be heavier that the one use in mobile, and even cumbersome in some cases.

Let's take the case of Field Days, these special events where many amateurs work outdoors. We observe quite often radio clubs or even isolated amateurs working with large antennas, verticals or beams. At such occasions, antennas are temporary fixed in the ground or at the rear of a van, ontop of a tree or on the building roof. Some teams do not hesitate to install HF beams which wingspan exceeds 8m or verticals 8m long that they place 5 to 10m high or on top of a crane shaft to benefit of a good takeoff angle in emission ! Of course setting such systems if you are alone in the field can be an impossible task, and each of us has to known his limits. In my humble opinion the maximum weight that a slender man can handle alone and quickly is about 15 kg to prevent any accident.

For the ease of working, this antenna should be omnidirectional but this design offers some drawbacks. As alternative the directive array must be light enough to be easy to rotate manually or using the lightest TV rotator. In that matter, I suggest you to read the next page to well understand what are the expected characteristics of a good rotator.

Selection criteria

Knowing these specs, in that range of products there are tens of antenna models : dipoles and wire antennas, verticals, beams, quads, log-periodics and even more exotic designs like rhombics, Moxons or rotary dipoles to name a few. The choice is huge, manufacturers as much; we have thus to reduce our scope.

I have chose six major arguments that might determine your selection :

- First there is the price that you want to invest in your antenna system. It will be surely your first criterion to consider : you could never beat the very cheap multi-band dipole or off-centered dipole, home-made or bought at 80-100 , but at another price scale you could never beat either the gain offered by a multi-element quad or a full length beam... In-between there are many multi-bands beams and quads, sometimes shortened (FD3, HF5B, TMG and alike), and many wire antennas and verticals.

- Then there is the kind of traffic and mode that you want to work, how far you want to emit, to work local QSOs or DX stations. If any stick work fine for ragchewing and offers report of "59" up to 5000 km away, sometime more, to work DX and break through pile-ups you need a performing installation, and very few amateurs using a dipole and low powers (QRP to 100W) can really compete against users equipped with big guns and amplifiers.

So in my mind there are only two possibilities to work pile-ups or DX stations without amplifier : in SSB using a gain antenna, what means using a directive array, or to work in CW with the hope that your DX will hear your "QRP" station emitting bare foot among all kW emitters, HI !

Personally I did the first choice for the pleasure to speak orally with my correspondent a few minutes. Of course many morsists will prefer by far to work in CW to be out of the phone QRM that we all have experimented one or another day working in SSB. It's up to you to select the mode in which you are at best.

- The bands coverage will be propably your third criterion : some antennas are multi-bands by design, others are mono-banders and need to add either new elements or some accessories to become true multi-bands (resonant). At last some models are so-called "multi-bands" but they must be manually adjusted to work on another band (changing a coil or moving it along the mast). Multi-banders and mono-banders have both advantages and drawbacks, the first for example will never offer the high efficiency (best SWR and higher gain) of the second, but it can work on several bands... This is a choice. However, I suggest you to use a mono-bander in a permanent installation or during a DX-pedition.

- The antenna design will also affect your selection. In a restricted space or for discretional reasons for example, a stealth antenna like a dipole, a vertical, a shortened beam or even a loop is very appreciated. Your municipality administration or even the owner of your house might also have edicted some strict rules in this matter. At last, if you work in the field, it can be also very difficult to handle the long elements of a beam, even shortened and so-called light, or the many wires of a quad if arms are not telescopic or wires/spreaders not pre-strung (hopefully, most are)

- Sizing and weight : depending on the design, some antennas are much more cumbersome than others, lighter or heavier than their competitors altough they display the same gain or the same radiation pattern. All this depends on the design, the material used, its quality and construction, parameters that affect the size and quality of the boom, the one of the mast as well as elements.

If it concerns a beam or a quad, its wingspan must be considered with care as its size and its weight affect the rotator power too, and increase the risk of torque. Of course, you will not be the first amateur to rotate manually your beam in the field.

At last the weight of your antenna has some influence on the wind load, and most heavy antennas do not support wind speed exceeding 170 km/h (110 mph) where a lighter model will do. So in case of doubt about the stability and sturdiness of your antenna, do install guy wires, otherwise you take the risk to see your beautiful antenna break in parts at the first wind gust ! Never forget that dame Nature is stronger that you and appear when you don't expect her. Remember Murphy's Law...

- Assembly time : due to their design, some models are quasi dedicated for permanent installations as you cannot necessary lost a full day to assemble then dismantle elements that request to be fine tuned or adjusted. Others, using material of poor quality, can be hard to dismantle once assembled or risk to be damaged. For short, the simplest and fastest will be the assembly, the quickest you will be on the air, and will be the dismounting in the same occasion.

So you will have to make compromises, and still compromises if you want to work on portable or from a restricted free space area, don't forget it. Of course the situation is much different is you work in a team on an open field, and if you can find some help to your friends to assembly and set up your antenna.

Usually an isolated person or a couple of amateurs can erect a 20m vertical or a beam made of titanium but you will need of 2 to 3 more people to erect a classic beam (> 20 kg), two participants erecting the mast while two others will pull on wires and check the system. In such circumstances, a good reflexion is mandatory prior any work and the use of a winch and some sturdy steel pulleys is recommanded. See my page about assembling an antenna system for more detail.

If you work alone in the field or at home, to avoid a possible accident or loosing time in assembling, better to use a light and short antenna, although this criteria is subjective (what is "light" or "short" for someone can be heavy or too long for another). Therefore we have also included such models in our selection.

For short I searched to meet the next criteria : I desired a HF multi-band antenna, if possible directional, offering gain, at moderate price (less than $500 if possible), light, that I can easy install anywhere and carry by car (inside) when dismantled in two or more parts, the longer elements (director or boom) being 4m long maximum (it must enter into a car, backdoor open or not).

I quickly realized that my selection was still very wide and had to be divided in two categories :

- The lightest and smallest HF antennas, not necessary the cheapest, but that you can handle alone in the field

- The (trans)portable HF antennas, that you can assemble alone but to use preferably in a semi-permanent installation due to their large wingspan or their weight or to use on a holiday spot or during a Field Day event helped by friends.

It is a subjective selection from which some well-known models have been excluded because their design was very close to the one displayed. I have tried to sort this list according to the performance and quality/price ratio, completed with their technical specifications and some comments.

To see : Operate a Remote station per subscription over Internet

Video tutorial, by Remotehamradio

The nec plus ultra of mobility. Above, a portable installation in its lightest version but relatively sophisticated using a remote connection. This amateur is using a Kenwood TS-480 portable transceiver fed with a 13.8V DC supply and only its standalone control panel. Its base and the antenna can be near or located thousand kilometers away. Indeed, thanks to an additional "Sky Command II" V/UHF transceiver (cf. instruction manual) or a remote module and optional software as described below, the control panel can be linked remotely to its base. The link is either RF or via a LAN or an Internet connection (using e.g. a Linksys Wi-Fi router). Watch this video on YouTube. In this configuration, the amateur can work from anywhere over the world while being connected to its base and antenna maybe located on the other side of the Earth ! Document EC1DJ adapted by the author and Remoterig.

Performance

The antenna gain displays in these tables is the value given by the manufacturer. In other words, a value measured in "unknown conditions of use" as most of them never list the heigth of the antenna and the soil properties. Their figures are thus more than probably subject to correction in your working conditions to... a lower value (usually 1-2 dB less). As we told previously, real gain values of some commercial antennas are available on various websites like DM2BLE, and technical design notes on L.B.Cebik's website, W4RNL (sk 2008).

Comparing apples and peers like beams vs. verticals or dipoles, or full length beams with shortened models is always unfair from one of another model and misleading. But it is generally well so that you and me select our antennas. We check first all existing designs, then we select a short list of models, then the item that fit our needs.

In selecting an antenna you must be aware of these "juggling numbers" and well understand what dbd and dbi units mean and how performances of an antenna system can be affected by many factors, the main one being the height above ground and the ground conductivity without forgetting the use or not of radials with verticals (see basics of antennas, the mystery of radials, All about transmission lines, etc).

Anyway, as told me Cornelius, DF2SA, "Guess I will never succeed convincing those marketing people not to exagerate so badly".

Here is my selection knowing that I am not in the business or in relation with these brands, and thus neither pro or con any brand in particular :

The lightest and smallest HF antennas

Model

Price

Comments

OPEK

HVT-600

$80

HVT-600 is a vertical antenna made in Taiwan. It is a mix between a screwdriver and a whip mobile antenna. It is compatible HF/VHF and cut at 1/4-wave. Its radiation pattern is omnidirectional.

It cover up to 9 bands : HF bands except WARC, plus 6m and 2m bands and sustains a power up to 200 watts PEP. It shows a low VSWR and breaks down to be easily carried in a small bag.

Its overall length is 1.62 m for the 80m band and 1.37m for the 10m band.

HVT-600 uses jumper lead to change the frequency band (what can become a tedious task when working in the field at night).

The base of the antenna is a male PL-259 connector and requires a SO-239 mount. This price does not include the base, the mount or the coax (that OPEK can provides as well). A Diamond, Comet, MFJ 5" Mag or other mobile mount can be used.

Note that this antenna has no flex at its base (so it can be damaged if it strike an object). When the jumper lead is too close to the mast and the antenna used without radials, it can also induce a high SWR.

Some amateurs use it attached to a back pack while walking, while the set up on a tripod, on the roof top or at the rear of a car (even on a ball joint) is the best method.

This antenna can support DX contacts up to 7000 km or more (e.g. US to Eastern Europe). 

HVT-600 is available to Universal Radio for $79.95, also on eBay.

Alpha EzMilitary

$249

The EzMilitary antenna from Alpha is a folding vertical able to sustain 500 watts PEP between 6 and 80 meters.

It can be installed and you can be on the air in about 90 seconds !

The kit provides all accessories in a 8x10x40 cm padded bag including the 3.9 m or 13' antenna that breaks down into 6x 38 cm or 15" sections, a marine grade shock cord, a Micro-Alpha Match with integrated SO-239 connector and 24x3/8 stud, a Universal Jaw Mount that allow to attach the antenna on any support, and an optional Counterpoise (add $50) very useful to reduce the SWR.

The best SWR depends on the configuration and specially the antenna height above ground and the use or not of the counterpoise (a long copper wire).

Indeed, at ground level, it will be hard to get a SWR better than 3:1. Installed 2 meters or more above ground, an SWR of 1.7:1 can be reached on HF bands, and 2.5:1 on 6 and 80 m. As for all verticals, a better SWR can be achieved using additional radials that also allow to use the antenna on the 160-m band. 

The EzMilitary is also available in Europe to WiMo fot 240

Note that HFPack provides similar solutions.

Buddipole

$400

Rotary dipoles (rotating) are not new. But this model is versatile and modular. It is made of aluminium and composite material. Collapsed its length is 56 cm and it reaches 4.9m full extended. Its weight is less than 1 kg.

The Buddipole coverage is 7 to 54 MHz in continuous, plus 144 to 148 MHz with a maximum power of 250 watts PEP. The SWR is under 1.5:1 and its gain is similar to the one of a dipole.

This is an excellent antenna for ragchewing and local QSOs but the Buddipole is able to support DX activities too.

Small, easy to setup and to collapse, it can be placed in horizontal or vertical position or tilted. It is sold with an optional tripod, a mast, rotator arms, and a stick among other accessories.

Without accessories it is sold about $200 (290 without options at WSPLC) but, minus side, using quality material the price double if you buy all accessories (the Buddipole package).

Hi-Q-Antennas

$500

Most mobile antennas are not DX-oriented due to their size. But some models sold by Hi-Q display an overall Q-factor of 580, one of the best in its category. They are also really quiet, without noise as we can expect using a vertical. Hi-Q antennas do not exceed a weight of 5 kg (10 lbs).

Most Hi-Q antennas can be manually or remotely auto-tuned but the remote unit requires to be powered (300 mA).

The model displayed is Hi-Q-4/80 RT (aka Hi-Q-PIRANHA-4/80) covering 10-80m bands. It comes with a 10x25 cm (4x10") loading coil. Note that Hi-Q-4/160 RT (10-160m bands) is similar in size.

These antennas are sold with an optional giant quick disconnect, a whip quick disconnect, a capacitance hat and a unun or a shunt to make the installation easier and get better performance. The optional top whip is not provided but can be purchased to any radio dealer.

Hi-Q has also build rotary dipole versions of his antennas (TAD, Tune-a-dipole), a good way to compete vs. Buddipole.

These antennas are best suited for ragchewing and local QSOs on low bands (160, 80, 75, 40m), but they all display good performance in DXing too. QSOs up to 10000 km away are not exceptional (ON to K, VE to 5X, K to UA, K to VK, etc).

These antennas can be used in a base station too. But knowing that they are designed for mobile installations, used at ground level, in an attic or on a balconery, if you want to work DX stations, you may need to install at the base a counterpoise made of several 1/4l radials.

The price listed includes all options (caphat, giant quick disconnect, etc), and add ~$45 for delivery.

Mizuho

PBX100-MK2

230

PBX100-MK2 is a short and light vertical antenna working on all HF bands from 80 to 10 m (including WARC bands according to the ads although some users did'nt reach the resonance on 17m).

Thanks to loaded coils, the frequency selection is automatic with a VSWR up to 1.1:1 with a couterpoise, the bandwidth depending on band.

Packed down, it measures about 1m in length. Its overall length is 3.60 m, it sustains a power of 200 watts PEP in SSB.

Amateurs working with 2.5 W worked G to UA with a report 55-56.

The antenna is delivered with a wire ground plane, a tripod and all necessary radial wire (counterpoise). Its weight is lower than 3 kg.

The PBX100-MK2 antenna is sold by WSPL in UK (160) under the nickname "Watson" and by Sardif in France (230) under the nickname "Cosinus".

WiMo GPM-1500

254

Very light (4 kg), small (6.3m high), stealth and very unobtrusive, WiMo GPM-1500 is easy to set as a fishing rod with simple screws and collars. It covers all bands from 1.8 to 30 MHz, and, with reduced efficiency, it works also on 50 MHz. This antenna sustains 200 watts PEP.

Made of 5 aluminium segments, it comes with a trap in the lower segment made of thick aluminium wire but without radials. Cut by design to work on all HF bands, it requires a tuner to get a good SWR as well as a counterpoise made of several 1/4l radials at the base. To work on low bands (160 and 80m), a radial over 10m long is recommended if the antenna is placed at ground level but it should be elevated to reduce ground effect.

Offering a gain similar to the one of a dipole (0.3 dBd) its sensitivity is on par with a dipole with of course a little more QRM due to its vertical polarization.

It works fine for DXing too but do not expect miracles and work a DX-pedition in the middle of the Pacific or you wil be really lucky.

Similar models or more performing are sold by Butternut, Cushcraft, Diamond, DX-SR, Force12, High-gain, Hustler and other well-known manufacturers. Some of these models look like flag poles (the radiator is inserted in a plastic or fiberglass tube) or do not use any radial or counterpoise. However to get optimum results, radials are mandatory with any kind of vertical shorter than 1/2l.

Princeton G5RV

50-60

The G5RV antenna is a dipole 31m long (102'). This multi-band antenna (80-10m) offers one of the best quality/price ratio and excellent performance when it is well feeded and placed high enough above ground (over 0.5l or at least 6m high).

This model is made of #14 AWG (inner 1.63mm) enameled copper wire (stranded), it is usually center fed with 10m (31') of 450 ohm balanced feedline (a ladder line) ended with a 4:1 balun and a SO-239 connector for the coaxial line.

Its main competitors are the famous W3DZZ dipole, Fritzel FD4, and the off-center fed Carolina Windom, this latter showing a more omnidirectional pattern and globally better performances. 

Wire antennas are usually installed in horizontal position ("flat-top") but they can be also placed in inverted V, inverted L or in slope, offering in that case some directivity. Dipoles can also be used as "wire beam" rigged in a shallow inverted "V" form and some amateurs like VE3RGW use them in arrays successfully too.

Generaly speaking, due to the ease of setup, its low profile and its very attracting price, the dipole is the most used antenna, and not only in the field or for portable operations. This is a must for receive purposes too and it can easily compete vs multi-band verticals or beam due to its less sensitivity to QRM and pick-up efficiency.

G5RB is sold by Universal Radio among many other dealers. Similar models are also sold by Ham Headquarters (Permo) in Norway.

WiMo BABY Loop

1060

The BABY loop from WiMo is an impressive magnetic loop of 1m diameter made of 60/60 aluminium of 50 mm diameter. The weight of this loop is also impressive, 12 kg, what requests a robust mast and maybe a tripod.

It works between 6.6.-29.7 MHz, supporting up to 1 kW PEP SSB on 10m (but its tuner supports only 250W).

The gain of a magnetic loop is similar to the one of a dipole. The F/B gain falls down from 4 to 0.3 dB from 7 to 28 MHz while the F/S gain exceeds 23 dB. Its SWR is modest, ranging between 1.2:1 and 1.8:1.

Minus side, magnetic loops are usually very expensive and emit a very intense magnetic field that requires to place them over 5m away from living beings if the power exceeds 10 W. A good security distance is thus 10m. It must be also connected to a 220V power supply.

Plus side it is very small and can be placed anywhere, at the end of the attic, on the balconery or on the chimney. It is sold with a remote controller. WiMo provides also a more weatherproof model and full automatic for 1200.

Note that WSPLC, DK5CZ, HB9CRU, HB9ABX, MFJ Enterprises or Amateur Radio Store (Alpha Loop) sell similar models too and sometimes much cheaper.

Due to their low profile and lightweight, all portable antennas reviewed above are small enough to fit in baggage on air transports without additional charge. It is a major advantage if you want to work on the air from a holiday and DX spot.

Indeed, these models can be used in the field successfully in their classic configuration or any variante (dipole in inverted-V or inverted-L, wire beam rigged in a shallow inverted "V" form, loop in horizontal position or installed indoors, vertical in arrays, etc). Out of the car, installed on the ground, a yard or on a terrace, and fully assembled all these antennas can be ready to work between a few minutes and a quarter of an hour maximum.

If you are searching for a portable gain antenna, for DXing or even to work contests, the ones listed above do not meet your specifications. I do not state that they can be used to work DX or contest stations but their performances are limited by design; they are not great competitors, but simply more adapted to local and regional QSOs. However, when propagation permits, they allow you to work stations located over 10000 km away, even if they receive you not loud always and clear.

Therefore in the next table I have listed larger antennas, light enough to be moved on portable operations but mostly designed for a semi-permanent installation (a week-end, on holidays, etc) or a field activity, and to work DX. These are shortened directional antennas and one vertical.

Next chapter

(Trans)portable HF antennas

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