Radio Orienteering

Amateur Radio Direction Finding (ARDF)

Welcome to Radio-O.  Here is how it works! We provide a radio receiver with a directional antenna, an orienteering map, a compass, and a finger stick. By pointing the antenna and listening to the signal you can determine the direction of the signal.  Using this information you navigate to the transmitter and punch in with your finger stick. Only the start and finish are marked on the map and it is important to keep track of where you are.  To qualify as finishing you must find at least one transmitter on your course and reach the finish within the time limit. To calculate results -- first; the number of assigned transmitters you found, then; your time on the course. We offer beginner through advanced courses, Regular BOK fees apply, and Pre-Registration is required.

Latest News in Radio Orienteering

October 26th, 2020

Radio-O/ARDF Eno – October 25, 2020 – Results

It rained, it rained, all day. But fifteen participants still came out to race for the foxes. There were slippery roots, muddy depressions, and pointy rocks hidden under leaves. During the post race discussions a number of adventures were recounted. With everyone staying in good cheer it was a super fun event. This was mostly […]

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October 15th, 2020

Open Radio-O/ARDF event at Eno River State Park, October 25, 2020.


Registration for this event is now closed.


We will have an 80 m classic course at the Eno River State Park Few’s Ford Access on Sunday, October 25, GPS 36.0742 -79.0055. For more information about Radio-O/ARDF, see the BOK ARDF page. Starts 10:00 AM to 1:00 PM. The course closes at 3:00 PM.

Some notes related to COVID-19. Pre-registration to a particular start window is required. Please bring a face mask and wear it when around others. Maintain social distance. There will be no class. There is only a classic course, no foxoring. We will meet by the parking lot. Maps and any reserved equipment will be set out next to our meeting place with your name and there will be a box to return your equipment when done. From our meeting place, you will have to walk to the start and back from the finish, both of which are on the west side of the Eno. The entire course is on the west side of the Eno. When approaching the bridge, please stay back from the end until others are done crossing. The homing beacon is the finish. There is only one control to punch at the homing beacon and it is the finish. There is no finish shoot.

Pre-registration: Register for your arrival time here.

Courses. There is no need to sign up for a particular course. Everyone gets the same map.

level distance foxes to get
1 fox 1.2 km . . 3 . . hb
2 foxes 1.9 km . 2 3 . . hb
3 foxes 2.6 km . 2 3 . 5 hb
4 foxes 4.1 km . 2 3 4 5 hb
5 foxes 5.1 km 1 2 3 4 5 hb
August 16th, 2020

ARDF Results Aug. 16, 2020

We had a beautiful cool day. It felt like fall with the sun behind the clouds. Charles Scharlau set the course and eight people went out. This event was set up like an official ARDF classic 80 m course with a start corridor, becon, and finish. People found anywhere from 3-5 transmitters. One interesting note, […]

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August 5th, 2020

ARDF August 16 at Gray Owl

The event will start at 8AM and Transmitters will go off at Noon. The beacon will stay on until everyone has returned. The location is 1725 Gray Owl Road in Asheboro, NC.

You must register for this event here!

Thanks for your input about start times and course lengths. Charles can now design the courses to create the choices we need.

The current plan is to have the start about a 1k walk from Gray Owl and the finish at Gray Owl. The swampy area in the north of the map will be out-of-bounds so that no one gets bogged down in it. 🙂

Charles wants this to be a championship level course with proper exclusion zones and start and finish corridors. Foxes will be at 3.54 MHz, and the finish beacon at 3.60 MHz. They will be 1-Watt transmitters operating into vertical dipole antennas. There will be an electronic starting “gun” providing start tones to inform participants when they may turn on their receivers and start.

The event will be open for a total of 4 hours. The first start will be at 8AM so we can avoid the heat as much as possible.

August 1st, 2020

Gray Owl Results ARDF & O 8/1/ & 8/2/2020

Most people came on Saturday and just a few on Sunday. We started at 7am so the early birds could stay cool. Even so the humidity was so high that we were soaked setting out the 1.6k ARDF sprint at 6:30, just walking. Some people had a problem with control #10, only on Red, and […]

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