WA7NBF ready to go

2007 USA ARDF National Championships

Sept. 14-16, 2007

Lake Tahoe, California

Perspective from Neil Robin, WA7NBF,
a participant


This is a brief report on the IARU/US National and Regional Championships held at Lake Tahoe on the above dates. 

Radio Orienteering is a sport that is much more popular in Europe and other parts of the world but slowly gaining interest in the US. It combines Orienteering with Radio Direction Finding. 

You will probably ask what is Orienteering?  In short , its  the athletic ablility to travel cross country to multiple control points in the minimum amount of time.  At each control point their is a type of recording device to show that you reached that point and your elapsed time.  Control points are only made known when you reach the "starting gate".  Of course, you can travel through thickets , brush, swamps or whatever to reach these points but a smart contestant will read the special orienteering map handed him once in the "starting gate".  Strategy is very important to work around obstacles.  Most will make use of trails and roads  to cover large distances quickly. A source of more information can be found at:  Orienteering

Radio Orienteering changes "control points" to hidden radio transmitters (foxes).  You have to use Radio Direction Finding (RDF) skills to locate these new points, then punch the clock as you reach them.  When you're handed the map, only the terrain is shown, not the location of the transmitters.  You must use your RDF skills to build your strategy and minimize the time needed to find all the required transmitters yet avoid obstacles along the way. Transmitters will almost always be hidden in the bush, not near trails or roads.  Of course, VHF radio signals bounce alot so taking bearings is a developed skill.   The winner is the one that finds the required number for his class in the least time. This arrangement is called ARDF or Amateur Radio Direction Finding and involves international rules. The US is part of region #2 but we use region #1 rules.  More info on this at: ARDF. Orieentering maps are built from topographical maps but symbols and legend are added to show detail that potentially limits travel or helps ID positions.  Once you start to travel cross-country you will almost always become lost in a matter of minutes.  You no longer know exactly where you are? Using the features of the map in coordination with what you see will help you reestablish or at least estimate your location.  For me, half the fun is figuring out where you are? A map example is shown below.

Orienteering map used in 2 Meter hunt showing only Start and Finish points

The color coding is much different from topo maps.  Dark green is very rough terrain with cross country travel being discouraged.  The "starting gate" is located in the lower left corner as a purple triangle.  The circle surrounding the start is the "exclusion zone" with a radius of 750 meters.  No transmitters will be found within this area.  The "finish" are the two concentric circles .  No transmitters will be found within 400 meters of each other or the "finish".  Thats what the smaller circle is all about.  When you're handed the map, you could guess where up to 5 transmitters are located but you will need RDF to pinpoint them over each 5 minute re-cycle period. The challenge is to reach each required and return to the "finish" in the least amount of time and before the course overall duration expires. Map legends can be found here.

The international rules control many aspects of the hunt: Rules.  No GPS usage is allowed and its an individual sport relying only on map, compass and RDF skills.  You can't attempt it as a team so you must travel alone but all have enough skill that getting lost would be rare indeed.

Partial Team Photo

2007 Lake Tahoe team

I'm located in the middle of the picture.

My Results

Bronze metal, 2007 ARDF contestI only entered the two meter contest although Dale Hunt , WB6BYU, loaned me an 80 meter receiver.  I didn't put the time into learning how to use it so I could compete effectively.  Nearly all competitors  were experienced enough that my practice was very important for any success that I could expect.  80 meters works differently then 2 meters in that you don't have the reflections but you also don't have a good indication of signal strength. In a practice session, I completely walked around a transmitter but couldn't tell how far away it was.  It turned out that I was nearly on top of it but didn't know that at the time.  Experience helps alot!

I won the Bronze metal for my M60 class in the 2 meter contest.  I was the oldest of the participants at the meet.  This class has limited number of participants since the race requires considerable physical endurance which discourages older folks.  Being an insulin dependent diabetic, I didn't want to push myself at the 6,500' altitude of Lake Tahoe so I took 2 hours to "finish".  I was very pleased that I made the metal round and have the utmost respect for the serious runners.  Most have been at it for several years.

The best of the US team still rarely wins world class metals .  The Europeans, particularly the Ukranianes, are the ones to beat on the world stage.  Orienteering and Radio Orienteering are sports that their high school students participate in so its very common activity for them as they grow up.

This event was sponsored by the Los Angeles Orienteering Club along with the Santa Barbara Amateur Radio Club.

Attendees included Brian Ackerly, VK3YNG  from Austraila.  Brian is most noted for his design and manufacture  of the Mk 4 "Sniffer" two meter foxhunting receiver.  Brian is so good that he competed in a lower age class just so he had to find all five transmitters.  He won the "gold" in that class! 

Joe Moell, K0OV the main author of the popular book,  "Transmitter Hunting " provided considerable volunteer support for the event.

One member told of disturbing a bear that was sleeping on one hunt. Glad the bear didn't follow him to the finish line!

Brian Ackerly, VK3YNG
Joe Moell, K0OV
Trainee & Bob Cooley
Typical transmitter site
Emerald Bay
Angora fire damage
Additional Photos taken by other participants can be viewed starting at: http://www.homingin.com/ltpix2.html

This links to further pages.

An article has also been written in the Fall 2007 issue of CQ-VHF magazine, page 63 about the event and changes to emergency transmitters