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Spider Beam Antennas

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Some hints and links on topics we have found by experience when operating portable

Power Supplies, Antenna, Filters, Transceivers

Operating portable is a challenge no matter how civilised the accommodation. The first and best advise is before you go assess what you need and make a list. Re-visit the list as you plan and your ideas evolve, it will be suprising how many things get added to the list as you go along. Hopefully a few get taken off. Do a trial run, set everything up in the back yard or local beach this will soon show up what you have missed or the deficiencies in what you are doing

Power Supplies

Working from a mains supply is of course the easiest and usually the most reliable. But before you go make sure the mains is actually available to you. Many remote area powers supplies are only run a certain times and the host might not welcome you running the generator all night to keep the linear going. A lot of remote area power supplies are based on solar power and the extra drain of a 100w transciever will probably be tolerated but not the 400w linear with a likely load of up to 800w on the supply.

The need to take a linear is questionable when working a rare location and propogation is good. As the station being chased being heard is not likely to be a problem unless you particularly want to work a certain area.

We have used a variety of methods for power in remote locations. The best method is to used 60-80AH deep discharge batteries charging them from solar panels. Most island locations are very quiet and using batteries does not create any man made interference. The disadvantage is that poor weather and lack of sunshine may result in charging problems. This can be resolved by using small portable generators such as the Honda EX7 or EU10i although keeping the Honda inverter generator RF quiet can be a problem. Adequate filters and long power cords are a must and try the set-up before you go. Do not be tempted to use cheap two stroke generators they will let you down. Ultimately the choice of power source will be governed by the method of transport and what you can afford. If you plan to use a switch mode power supply make sure it is RF quite before leaving home.


The biggest and the best you can afford and can transport is the best solution but getting them onto an island can be interesting. As has often been stated the easiest way to improve station performance comes with improvements in antenna. We have transported and set up HF tribanders in the past but they are heavy and awkward to use. Our current chioce is to use Spiderbeams . These are lightweight and pack away to an easily transported bundle. When combined with one of the excellent telescoping towers that Spiderbeam also supply the system is hard to beat.

For the lower bands we have used dipoles with mixed results most likely due to poor radiation angles as it is hard to get enough height above ground. The better antenna for 40 and 30 metres is a vertical and the Sigma XK40 has proved a winner.


If you plan to have more than one transceiver in operation and cannot get good separation between the antenna then bandpass filters are a must. We have used filters with good results and also built our own, see separate page. These filters are highly effective and on the trip to Dirk Hartog Island allowed two operators to work 20 and 15 metres without interference to each other and with the antenna less than 10 metres apart.


The choice is yours but the most practical for island work is the compact HF transceivers such as the Icom IC706, IC7000 or the Yeasu FT857. These radios are easy to tranport and use and generally very reliable.

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