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

June 2nd, 2020

ARDF/Radio-Orienteering – 80m Classic at Carolina North Forest – 2020-05-31 – Results.

We had a nice day of radio-orienteering at Carolina North Forest. We had ten participants come out to search for foxes. The rain finally stopped the day before. The ground was still pretty wet but the temperature was wonderful. We have pictures from the event here. It was down-sized 80m classic. Shorter distances. No start […]

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May 17th, 2020

Radio-O/ARDF event at Carolina North Forest, Sun. May 31.

We will have an 80 m classic course at Carolina North Forest on May 31. Park at the parking lot at the end of Municipal Drive (GPS 35.9365 -79.0661, Google maps link). Then follow the BOK signs to pick up your map. There is a ten minute walk from the pick-up area to the start. For more information about Radio-O/ARDF, see the BOK ARDF page.

Starts available from 10 AM to 2 PM. You must register for a specific 1-hour start window. Registration for a start window will close when six people have registered. If you need a receiver, it will be possible to pick one up with your map. Bring your own earphones. Additionally, there is a park-specific indemnity waiver to sign when you pick up your map. Bring your own pen. If you would like to print your own map and waiver, add a note in the comments and we’ll send you copies by email.

All courses use the same map (8.5×11 inch, landscape, 1:10000). Depending on the number of controls you go for, the course lengths will be 4.7 k (5 foxes plus the homing beacon), 4.0 k, 3.5 k, and 1.8 k (2 foxes plus the homing beacon).

You can register for the event here.

May 3rd, 2020

Results 05/02-3/20 Orienteering & ARDF

Charles set a flawless 6k classic ARDF course on Saturday – further testing his newly built equipment. We hope he will keep modifying and testing (after all, think about how many events are necessary to prove they are durable). Joseph & Ruth set Sunday’s courses including a complex ARDF FoxOring. The Orienteering courses included a […]

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April 20th, 2020

Gray Owl 4/19/20 ARDF Results

We had another perfect ARDF event. This time we used, for the first time, transmitters and antennas that were built by Charles. The event came off without a hitch. The antennas are unique. About a year ago I wondered if we could have antennas that didn’t need a ground wire. This wire needs to lay […]

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April 7th, 2020

Orienteering & ARDF April 18-19 at Gray Owl

Saturday, April 18 This is no longer an Open event. We will have an Advanced orienteering event at 1725 Gray Owl Road, Asheboro. (Orange through Red courses) We have a new sprint map of the Rock Garden, a complex area with many rock and rootstock features mapped at 1:4000 by Vladimir Lyuk. The plan is to start with a ~2k sprint at the Rock Garden and when the last sprint control is punched the course will continue with an appropriate length Orange, Brown, Green, or Red course back to the finish at the house. Start window will be from 10am – 2pm to spread people out. You must register for starting during a particular hour. Choose the hour you want to arrive when selecting the product for registration. There is a limit of 6 entries per hour. Course closes at 4pm. Maps will be pre-printed or you can request a PDF when you check out if you want to print the map yourself. Each day requires separate registration. Register for the Orienteering event on April 17 by Choosing the “Product” that represents the hour you wish to arrive. Registration closes at 5pm, Friday April 17, 2020

Sunday, April 19 we will have a classic ARDF Event set by Charles. Check out the details below. Register for the ARDF event on April 19 Registration closes at 5pm, Friday April 17, 2020 (If you are coming on both days you must register for each day separately.) Start window will be from 10am – 2pm to spread people out. (Since we only expect 10 people separate arrival times are not necessary.) Maps will be pre-printed or you can request a PDF when you check out in the notes if you want to print the map yourself.

ARDF details for the event:

Transmitters will be synchronized closely with UTC. So if you want to have a genuine championship experience, then go to the Start and then turn on your receiver at a five-minute multiple from the top of the hour. You will hear transmitter 1 start at the top of the hour, five past, ten past, etc.

Start and finish corridors will be marked with tape. The finish transmitter will be at the entry of the finish corridor, and the finish SI box will be at the finish line.

Transmitter power will be 1.5 Watts. Frequencies: 3.57 MHz foxes; 3.60 MHz finish beacon. Antennas will be 20-foot long vertical dipoles with no ground radials to trip over.

Finish will be at Gray Owl (35.631319,-79.883209). Start will be within 300 meters of the trailhead off Tot Hill Farm road (35.6367311,-79.9046895) It is a little over 2km walk from the Finish to the Start, only partly along mapped trails. So competitors walking from the Finish to the Start need to able to orienteer to the Start and allow time for the trek.

Control Assignments: M70 and W55 will skip Fox #4. W65 will skip Foxes #2 and #4. M40 will skip #2. (This may change depending on registrations.)

The youth course will be near the finish area described above and will be about 3.5 km effective length. Start and Finish for the youth course will be at Gray Owl.

  • Our plans for COVID safety:
    • Only 6 entries may arrive and start per hour
      • Choose the correct product for your preferred hour for Saturday.
    • We will ask people to stay outside of the house except for using the downstairs bathroom.
    • We expect everyone to maintain a minimum of 2m distance from others.
    • We will not rent finger sticks or loan compasses.
    • We will rent receivers
      • Bring your own headphones
      • Bring wipes to sanitize the receivers before and after use.