About T-Hunting

Transmitter hunting, or "T-Hunting," also often referred to as "Fox Hunting," is an enjoyable combination of  Radio Direction Finding (RDF) techniques, orienteering, healthy exercise, fun in the fresh air, and good friends from all walks of life. AZTHunt utilizes small, low power transmitters hidden in public areas such as a large regional park and the "hunters" seek them out using easily constructed equipment along with a hand-held radio receiver. Around the world T-Hunting ranges from smaller casual hunts, such as those typically sponsored by AZTHunt, to national and international championship competitions. Additionally, T-hunting skills are often used in search and rescue work, wildlife tagging applications, and tracking down interfering signals in both professional and amateur radio communications systems.  T-Hunting participants are not required to possess an amateur radio license and the skills are easily learned.

The typical T-Hunt sponsored by AZTHunt may be a larger scale "driving" hunt where multiple transmitters are located within a three to six mile radius of a starting point, or a walking hunt where several transmitters are hidden within walking distance. Driving hunts often also include the multiple transmitters of the walking hunt at a single main transmitter site once it is located, and those who prefer only the walking portion may proceed directly to the hidden transmitter area. Other options are available and we are always open to new adventures!

T-Hunting Equipment

While there are several sophisticated options when it comes to RDF equipment, successful T-Hunting is easy to accomplish with simple to construct, do it yourself (DIY) equipment. One of the more popular options is the "Yagi-Uda" antenna. The Yagi, as it is often referred to, was invented by Dr. Hidetsugu Yagi and Dr. Shintaro Uda of  Tohoku Imperial University in 1926. This antenna design creates directional characteristics allowing the antenna to point in the direction of a transmitter. Yagis are easily constructed utilizing segments of tape measure for elements and common PVC pipe as a support frame.

The Yagi in the photo above was easily constructed from common materials using plans from Joe Leggio WB2HOL and includes a variable attenuator to allow the antenna to continue to be effective when getting close to a transmitter. Check out the Links page for links to these and other options for DIY equipment.  Keep in mind that AZTHunt can always provide loaner equipment on our T-Hunts for those who would like to give it a try. 

Tracking Down the "T"

Armed with the directional Yagi or other RDF equipment the hunter is led to the transmitter by taking directional bearings using the signal strength of the received transmitter signal. On a longer-range driving hunt or a walking hunt in a localized area, the techniques are much the same. Using directional bearings to "triangulate" the location as the hunter gets closer and closer to the transmitter; the "T" will eventually reveal itself!

Google Earth imagery utilized per Google attribution requirements.

In the example photo above, three bearings are taken while tracking a transmitter in Chandler Veteran's Oasis Park to determine the transmitter is likely located within the "triangle" created by the intersection of the three bearings. 

What Does the "T" Look Like?

While a longer range driving hunt transmitter will differ in size and configuration, the typical AZTHunt walking hunt transmitter looks like one in the photo below:

This small device transmits with a power of 15 mW in the two-meter amateur band (146 MHz) and, depending upon the type of antenna attached and how high it is placed, may be heard for several miles. Transmissions repeat on a timed cycle, and tones easily identify  it as a T-Hunt transmission along with the FCC required Morse code identification. The transmitter shown here is a Micro-Fox 15 courtesy of Byonics, providing equipment to AZTHunt and other fine electronic projects for amateur radio. 

We hope this brief introduction to T-Hunting has sparked your interest to join us on our next T-Hunt! Like most things, it is more difficult to explain than it is to do and AZTHunt is always glad to meet new friends who enjoy a fun outing. And, as we state on our home page, T-Hunting is a great way to grab some fresh air, enjoy the company of great friends, have fun with technology and simple DIY equipment, and does not require participants to have an amateur radio license or technology experience.