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

May 7th, 2019

2m Practice

We had a successful practice Monday evening (5/6/19). After Imre and I set the transmitter on the side of a steep re-entrant, Ruth and David joined us in a walk around the transmitter that went through a large re-entrant and over and behind a ridge. The goal was to gain some experience determining which signals were pointing toward the transmitter and which weren’t. What was particularly enlightening was having the four of us standing just a few meters apart and getting very different signal bearings. Because we marked the location of the transmitter on our maps we knew which signals were reflections. We didn’t figure out a great way to distinguish the correct signal, but the most successful technique was keeping track of the various signal bearings and choosing the bearing that came up over and over again. The reflections didn’t tend to come from the same location as one moved – even just a few meters. Next in line was walking toward the signal – the accurate signal was more consistent as you walked toward it than the reflections. One surprise was that using the polarized characstic of the signal was less effective than we expected. While the correct signal almost always quieted when the antenna was rotated vertically many of the reflections behaved similarly. We confirmed the general knowledge that until you get quite close to the transmitter, you can never be 100% sure that you have a correct 2m signal bearing. As you collect more information you improve the probability that you are correct, but until the gain is down to 1 or 2 and it is screaming, you are never 100% sure.

The next time we do this two of us will each put out a transmitter. That way we can do a reflection analysis on the transmitter we have marked on the map and in addition have a chance to analyze the signal and find the one at the unknown location.

Advance notice of this practice was sent out on the BOK ARDF list. If you didn’t get a notice, and would like to be added to the list, just send a comment to this article and I will add you to the list so you can get future notices

April 1st, 2019

2019 ARDF US and Region II Championships

Link to Bulletin 2

All of the Bulletin 2 details can be found in this Google Doc.

Registration and Payment can be found on the OUSA site:

Use this link to see who has already registered:

Organizer Contact Information

Backwoods Orienteering Klub
Ruth Bromer, Registrar,
Joseph Huberman, Event Director,
904 Dorothea Drive, Raleigh, NC 27603


(Subject to change)
● Saturday July 27: ​Arrival and equipment check 2pm – 6pm Lake Crabtree Park
● Sunday July 28: 9am​ – FoxOring Practice, ~3k Schenck Forest
4pm​ – Sprint Practice, ~2K 6pm Blind ARDF Practice (sighted may participate blindfolded) Dorothea Dix Park
● Monday July 29: ​ 9am 80m Practice ~4k, Umstead West
● Tuesday July 30: 9am 2m Practice ~4k, Umstead West
● Wednesday July 31 ​ : Rest Day, Arrival, equipment check, 2pm – 6pm Lake Crabtree Park
Meeting 8pm La Quinta Inn and Suites!
● Thursday Aug. 1: 9am ​ FoxOring Championship, ~8k Eno River State Park
● Friday Aug 2 ​: 9am Sprint Championship, ~3k, Pullen Park
3pm Blind ARDF Champs, Pullen Park
4pm – 6pm Classic 2m & 80m equipment check, Lake Crabtree Park
8pm Meeting
● Saturday Aug 3: 9am 2m Championship, ~8k Umstead North
● Sunday Aug 4: 9am 80m Championship, ~8k Umstead South

T-Shirt Design


$150 includes all events, Banquet and T-shirt.

Practice events Sunday – Tuesday
FoxOring $7.50
Sprint $7.50
80m $7.,50
Blind ARDF no charge
2m $7.50
Championship events Thursday – Sunday
FoxOring $15
Sprint $15
Blind ARDF no charge
2m $25
80m $25
Banquet $25
T-shirt $15
Late Fees after 7/14/2019 Midnight
Championship Events $5 each
Practice events no late fee

March 18th, 2019

Radio-O 2019 March 17 ARDF

We had a great ARDF event at Umstead Park on Sunday. We had 9 groups on the 80m classic (one group didn’t download) and 3 on the sprint. While this doesn’t sound like many, it really is a lot for a local ARDF event. We used all of our receivers, and where people went our […]

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February 25th, 2019

Radio-O March 17, 2019

We have a 80m ARDF event on March 17 at Umstead West. There will be a Classic 80m event and a Sprint. Everyone is welcome. We will have a beginner class at 12:30. We will rent receivers for $5 at the event.

Please pre-register for this event here, and when you choose your course choose whether you need to rent a receiver. You can decide exactly which courses you want to take at the event. You can do both the classic and sprint for the same entry.

Course lengths:
Classic 80m
5 controls is 5k,
4 controls is 3.7k
3 controls is 2.9k.
Sprint 5 controls 1.7k

We Got New Equipment

We bought a set of transmitters. They can be programed together using the computer or individually with their controller (the one on the left). We also have poles to mount the antennas, and it takes about 3 minutes to set up the transmitter and antenna in the field. The transmitters can broadcast either 80m or 2m depending on which antenna is plugged in. I have been testing them and we will use them for their first event on March 17.

February 9th, 2019

BOK 2019 ARDF US & Region II Championships

The Backwoods Orienteering Klub proposes hosting the
2019 US and Region II Championships.


July 28 – August 4, 2019

In and around Raleigh, North Carolina. All the venues are within a 30 minute drive from RDU airport and downtown Raleigh. There are many hotels and restaurants to choose from. All the maps are to IOF standards and previously used maps will be available to all participants.

Organizer Contact Information 
Backwoods Orienteering Klub 
Joseph Huberman, Event Director, 
Ruth Bromer, Registrar, 
904 Dorothea Drive, Raleigh, NC 

Proposed Schedule:

  • Saturday: Arrival and equipment check
  • Sunday: Morning – FoxOring Practice ~3k Afternoon – Sprint Practice ~2K
  • Monday: 80m Practice ~4k, Blind ARDF Practice (sighted may participate blindfolded)
  • Tuesday: 2m Practice ~4k
  • Wednesday: Rest Day, Arrival, FoxOring & Sprint equipment check, Meeting
  • Thursday: FoxOring Championship ~8k
  • Friday: Sprint Championship ~3k, Blind ARDF Champs,
    Classic 2m & 80m equipment check, Meeting
  • Saturday: 2m Championship ~8k
  • Sunday: 80m Championship ~8k

Everyone is welcome 
We will include the youth and adult categories for all the events. There will be awards for the top  3 in each category. There are no restrictions to enter. International teams can be any size. 

All the venues are within a 30 minute drive from RDU airport and downtown Raleigh. All the maps  are to IOF standards and previously used maps will be available to all participants. Subject to  permitting these are the venues we expect to use. 
Schenck Forest 
Dorothea Dix Park 
Umstead Park 
Eno River Park 
Carolina North Forest 
Pullen Park 

$150 includes all events, banquet and tee shirt. 
Entry cost for just some events have not been determined 
A $20 late fee goes into effect 6 weeks before the event. 
You must make your own arrangements for transportation, accommodations and meals. There are  many hotels and restaurants to choose from in the Raleigh area. Easy access to I40 on the west of  Raleigh is desirable. We will announce the Event HQ Hotel when the arrangements are made. We  will be happy to assist in making reservations for our international visitors.

International participants who need invitations and/or assistance to get visas should contact the  organizers.