Amateur Radio Field Days
While most base stations at the home QTH are indoors and supported by mains power and all modern conveniences, ‘Outdoor’ means working away from both the mains power and modern conveniences. That is not to say ‘Outdoor’ operating must be uncomfortable – quite the reverse. Just as we make ourselves comfortable while picnicking, camping or bushwalking, so does the outdoor radio operator seek to be well organised and comfortable within the constraints of why the outdoor operation is being undertaken. Organisation is a special feature of Outdoor operation – who wants to realise a fuse has blown and it’s 80km down a rough track to the nearest supplier and the BBQ has just been fired up..
Well, it’s a challenge. And because it’s there. It’s part of amateur radio to be able to operate under different conditions in for instance emergencies or while travelling. It’s sometimes more convenient to operate mobile or portable or from a field set up.. Mobile operations infer you are operating from some vehicle and it can be from your car, truck or bicycle , sailing in your boat or any other variation giving you mobility. Portable can be from a hand held or back pack or set up for field operation in a semi fixed location for some special event or because you are holidaying in the Kosciusko National Park or carrying out geological explorations in the Simpson Desert.
Most amateurs will operate mobile from a motor vehicle on 2 metre and/or 70m cm bands but also often on HF bands where more sophisticated antennas and tuning devices are required. Power comes of course from batteries charged from the engine alternators . While sometimes the antenna and installation will be home brewed, mostly mobile operators are using commercially supplied antenna equipment and radios
The challenges increase as the operator moves away from the motor or other vehicle with it’s inbuilt facilities and moves to being portable. In the case of a field activity being set up in a comparatively isolated environment, the operator must ensure power supply sufficient to maintain the operation of the radio for the required period, must make sure the radios and equipment being used are not too hungry for wattage, must make sure the antennas meet the conflicting demands of efficiency and portability and must ensure that all spares and support material are provided. Power is usually batteries with recharging by a portable petrol generator ( if sufficient porters are available to carry it to the site.) or solar panels or wind generators. Pedal power has of course also been a traditional way of charging batteries. Antennas for HF bands are usually dipoles or long wires strung between trees or, if you are in a treeless desert, laid along the ground.. If more sophisticated equipment can be carried, there are a range of portable dipoles for HF work. The VHF and UHF bands allow smaller and lighter antennas and often portable work by the serious operator will use a Yagi or similar beam antenna. Of course if operating portable in the microwave bands, the equipment becomes a a bit more complex but nevertheless fully portable to the enthusiast.
Trials and Tests
Because of the importance of mobile and portable operation capability for emergency communications, the Wireless Institute Civil Emergency Network (WICEN) conduct regular field trials to test and evaluate the performance of operators and equipment. The WIA also conducts from time to time field contests, principally the John Moyle contest, which is an Australia wide activity held in March of each year to encourage and provide familiarisation with portable operation, and provide training for emergency situations. The rules are designed to encourage field operation.