Open ARDF Ranking Event and Expert Long Form Orienteering at Umstead North

Filed under: Latest News,Radio Orienteering by Joseph on March 3rd, 2020

Registration Closed 6:30 pm 3/14/20

  • When: March 15, 2020 Courses open from Noon – 3:30 pm
  • Location: Umstead North, Multi Use Parking Area
    GPS Coordinates: 35.867674, -78.752441

Frequencies: Beacon 3.59Mhz , Beginner 3.55 Mhz, Expert 3.51Mhz

We will have Beginner ARDF (Radio-O) through Expert ARDF as well as Expert Long Orienteering courses.

ARDF (Amateur Radio Direction Finding)

Beginner and Intermediate ARDF

The Beginner and Intermediate ARDF courses will use the low power transmitters on a 2.5 minute cycle. There are 5 foxes and an Effective Length of 3.9 k. Effective_Length=Length+(Climb*10) . Each transmitter will be on for 30 seconds before the next one starts. That is plenty of time to get a bearing and you don’t need to wait so long for it to come back on again.

We will have 80m Receivers for rent and instruction on how to use them throughout the event. Bring your own headphone to use with the rental receivers. This is a good event for you to try out Radio Orienteering because we are offering a classic beginner course.

Beginner level courses – Foxes 3.55 Mhz – Beacon 3.9 Mhz

Course options (with effective length (length +10*climb):

  • ARDF Beginner White, 1.6 km, 2 foxes
    • 1, 5
  • ARDF Beginner Yellow, 2.5 km, 3 foxes
    • 1, 3, 5
  • ARDF Beginner Orange, 3.1 km, 4 foxes
    • 1, 2, 3, 5
  • ARDF Beginner Long Orange, 3.9 km, 5 foxes
    • 1, 2, 3, 4, 5

Be sure to Rent your Receiver (and bring your own headphone) when you Register for the Event

In ARDF you don’t need to find all the controls to successfully complete the course. The only requirements are: 1) Find one transmitter; 2) Find the beacon, which is close to the finish; 3) Finish within the 3 hr. time limit.

It may be harder than you expect, so don’t get discouraged. The trick is to get a direction bearing to the fox (fox is a common term for the transmitter) and draw it on your map. Now you can keep going toward the fox even when it is not transmitting. You can also take bearings to a transmitter that you are planning to find later. In the best case you can draw two bearings from different directions to get a cross bearing. This intersection of two accurately drawn bearings will give you the location of the transmitter so you can plan the best route choice to find it.

Many thanks to Imre for designing and setting the White – Orange ARDF courses and the Brown orienteering course. (This gives me a chance to practice on the ARDF Orange course.)

Expert ARDF Ranking Event

Expert level courses – Foxes 3.51 Mhz – Beacon 3.9 Mhz

This will be an ARDF Ranking Event for the following Categories:

  • ARDF Red 5 Foxes – Effective Length 8.0k, 5 Foxes
    • M40, M19
    • 1,2,3,4,5
  • ARDF Green Long 5 Foxes – Effective Length 7.5k, 5 Foxes
    • W21
    • 1,2,3,4,5
  • ARDF Green Short 4 Foxes – Effective Length 7.2k, 4 Foxes
    • W19, W35, M50
    • 1,2,3,5
  • ARDF Brown Long 3 Foxes – Effective Length 5.7k, 3 Foxes
    • W45, M60
    • 3,4,5
  • ARDF Brown Short 3 Foxes – Effective Length 4.8k, 3 Foxes
    • W55, W65, M70 
    • 2,3,5

The Advanced and Expert ARDF courses will use 3 watt transmitters and they will be on the standard 5 minute cycle with each transmitter on for 1 minute at a time.

ARDF USA Ranking Events

This event will be the first ARDF USA Ranking Event. The ARDF rules now include a subset that focuses just on the competitive standards of the race. This is to set a standard for championship level events, distinguishing them from practice events. The goal is to fairly compare competitors running in different local races as well as the US Championship events. The method for computing this is under development, but the standard for the races is approved. By holding, and reporting the results of the Ranking Events, we can collect the data necessary to develop the Ranking method. The goal is to have a National Ranking that can encourage more championship level events and assist the Team Selection Subcommittee with their decisions.

Long Form Orienteering

Long Form Orienteering has long legs and fewer controls. Route choice is thus more important.

There will be a 9.1k Red course with 6 legs ranging from 800m to 2.4k. The 7k Green course with 5 legs is similar except for one short 600m leg. The Brown course is a 6 leg classic format at 3.1k. Unfortunately Brown doesn’t lend itself to the long form.

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