Have you discovered the fun of hidden-transmitter hunting? ARRL Amateur Radio Direction Finding (ARDF) Coordinator Joe Moell, K0OV, debuts a new column on this fascinating facet of Amateur Radio that you don't even need a license to play!

Four competitors, each in separate age/gender categories, await the starting tone for the 2-meter event at the 2005 USA ARDF Championships: (L-R) Emily DeYoung, K4MLE; Vadim Afonkin; Mike Cegelski, K8EHP, and Dick Arnett, WB4SUV. [All photos by Joe Moell, K0OV]

Whether you're young or old, a new ham or old timer, a techie or an appliance op, radio direction finding (RDF) activities can add hours of fun to your radio hobby time.

To hams, foxhunting isn't a sport for horses and hounds. Instead, it's the mystery of hide and seek with radio gear, with boundaries ranging from a small park to several states. Just like Field Day, foxhunting gets you out of the shack and into the great outdoors, where you join with your fellow hams in person to test your abilities and engage in friendly rivalries.

T-Hunting Any Given Weekend: Mobile or On Foot?

Every weekend across the country, hams gather to compete against one another, trying to improve their RDF equipment and skills. It began at ARRL conventions in the 1930s, when they used crystal-set receivers to figure out which room of the hotel contained the transmitter. In the 1950s, their cars with strange loop and ferrite rod antennas for 75 and 10 meters prowled the streets in the afternoon and evening hours. By the 1970s, most of the mobile "T-hunt" action had moved to the 2-meter band, where Yagi and cubical quad RDF antennas made for even bigger stares and exclamations from passers-by.

Visiting radio-orienteers from around the world are welcome at national and IARU regional ARDF competitions. Ready to start on 2 meters at the 2005 USA and IARU Region 2 Championships are (L-R) Jay Thompson, W6JAY, of California; Bryan Ackerly, VK3YNG, of Australia, and Karolina Sucha of the Czech Republic.

Mobile T-hunting continues to grow in popularity, with active groups everywhere from metro areas such as Los Angeles and Chicago to the plains of Nebraska. Hams are using the skills they learn on these hunts to find sources of intentional and unintentional interference, to aid in search and rescue, and to help wildlife researchers.

I have enjoyed doing all these things for many years, and now I've found another way to have even more fun chasing transmitters. This "new" way doesn't require a vehicle, so it's suitable for hams and potential hams of all ages. It presents the opportunity for competition not only among the hams of your town, but among hams from all over the world. This radio sport goes by several names, including foxtailing and radio-orienteering, but is best known as ARDF--short for Amateur Radio Direction Finding.

Hams go on mobile T-hunts in just a handful of countries, the most prominent being the US, Australia, and the UK. On the other hand, more than 30 countries are active in ARDF. It takes place large woods and parks, with everyone on foot using a map and compass to navigate. That makes this sport similar to orienteering, except that instead of locating the "controls" using marks on the map, the hunters are using an unmarked map and RDF gear to locate up to five "fox" transmitters in a period of two hours or so.

A Little ARDF History

ARDF began almost 60 years ago in Scandinavia and spread across Europe. Competitions between nations soon followed, with the first World Championships taking place in 1980. International competitions required a standardized set of rules, which were developed and are revised as necessary by a committee of national ARDF coordinators organized by the International Amateur Radio Union (IARU).

In a clearing of the New Mexico forest, Jennifer Harker, W5JEN, of Texas stops to take a bearing. She's on the way to a gold medal finish in her category.

ARDF can be an activity for the family: Brian DeYoung, K4BRI, is about to cross the 2-meter finish line at the 2005 USA Championships (his daughter Emily is shown starting in a previous photo). On a championship course, each person must do his or her own RDF and navigating. No assistance is allowed. In contrast, informal local events usually permit pairs and small groups to hunt together.

At formal ARDF competitions, the hunters are separated by age and gender, with medals or other awards for winners in each category. Under IARU rules, only males between ages 20 and 39 are required to find all five "foxes." Those in other categories must only locate three or four. The object for each competitor is to be the first to punch in at all of his or her required "fox" transmitters and then get to the finish line.

ARDF began on the 80-meter band. Today's championships feature separate events on 80 meters and 2 meters. I will have more details of the present and proposed ARDF rules in future ARDF Updates. There's a lot more information on my Homing In Web site.

Mind and Body

ARDF is both a mental and physical challenge. It takes skill to get proper bearings, plot them, set a course and navigate through the woods. It also takes physical conditioning to do it faster than your fellow competitors. Perhaps you or a fellow club member has what it takes to become an ARDF champion. Your children and grandchildren might, too. Remember, no ham license is needed to receive and track these fox signals.

You don't have to be a combination of rocket scientist and marathoner to have foxtailing fun. There is a lot of trotting, walking and pausing on the course, plus a lot of head scratching when the bearings don't make sense. There is also immense satisfaction for everyone who completes the course, no matter how long it takes.

ARDF Championship Competitions

Stateside hams have been competing in the ARDF World Championships since 1998, and we have had our own national championships every year since 2001. This year's event was put on by Albuquerque Amateur Radio Club (AARC) and was combined with the IARU Region 2 (North and South America) ARDF Championships.

The sixth annual USA Championships will take place April 7-9, 2006, in the North Carolina Piedmont, and you're invited! The competitive courses will be open to anyone of any age, with or without an Amateur Radio license. Radio-orienteers from all over the country plus visitors from abroad are expected to attend. Medals will be awarded in the IARU's five age categories for males and four for females.

After the foxes are found and the competition is over, it's fun to compare routes and techniques with the hiders and your fellow hunters. Silver medalist Marvin Johnston, KE6HTS (left), and course-setter Jerry Boyd, WB8WFK, look over a map of the 2005 2-meter championship venue near Albuquerque.

Matthew Robbins, AA9YH (right), won a silver medal on 2 meters and a bronze medal on 80 meters at the 2005 USA ARDF Championships. Awards were presented by New Mexico Section Manager Bill Weatherford, KM5FT.

"Piedmont" is a French word meaning "foot of the mountain." This region, in the foothills of the Appalachians, features rolling hills and beautiful forests. The 5300 acres of William B. Umstead State Park near Raleigh International Airport are ideal for orienteering of all kinds. Backwoods Orienteering Klub (BOK), which claims to make the best forest maps in the world, will supply recently updated course maps.

The Championships start on Friday at noon with an optional four-hour practice and equipment checking session, followed at 5 PM by an information and safety briefing. The 2-meter competition takes place Saturday, and the 80-meter event will be on Sunday. In addition to the ARDF competitions, there will be a picnic get together on Saturday night, and an award ceremony following the 80-meter hunt. It will end in time for those who must depart Sunday afternoon.

Event organizers are Charles (NZ0I) and Nadia Scharlau of Chapel Hill, North Carolina. Both have been consistent medal winners at previous USA Championships. They attended the World ARDF Championships in 2002 and 2004, where Nadia was among the top six finishers in her category on one band each time.

The 2006 USA Championships take place early in the year to allow time for final selection of ARDF Team USA members, who will travel to Primorsko, Bulgaria, for the 12th ARDF World Championships from September 12-17. USA's team positions will be filled based on performances in last year's USA Championships in New Mexico and the 2006 events in North Carolina. A maximum of three competitors in each age/gender category may be on a nation's team.

Latest event information, detailed schedule, frequencies, and registration forms are in the 2006 USA ARDF Championships Web site, which also offers suggestions for nearby lodging and dining. Note that an embargo on the park is in effect. This means that anyone competing in these championships must not visit wilderness areas of Umstead Park between now and the time of the events.

Just Ahead . . .

Besides the latest radio-orienteering news, future editions of "ARDF Update" will have more on the history of ARDF, simple equipment to get your club started in the sport, training ideas, youth involvement, and so forth. Again, there's a lot more information on my Homing In Web site.

I'd enjoy hearing about RDF activities in your local area, so please e-mail your news and photos. Until next time, happy hunting!

About the author: Joe Moell, K0OV, went on his first hidden transmitter hunt on 75 meters at age 11. That event and other youthful ham radio projects led him to a lifelong career in electronics and communications. Still fascinated by the technology and techniques of RDF, he has written a book, a subchapter for The ARRL Handbook, a Web site and more than 190 magazine articles on the subject. In 1998, the League named Moell ARDF Coordinator to bring the US into the community of nations active in the sport and international foxtailing competitions. Joe lives in Fullerton, California with wife April, WA6OPS. When not hunting transmitters, hiding them, or trying to convince other hams to try the sport, they organize local hams to support the emergency communications needs of Orange County hospitals.

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