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Presents a practical design for a **crossed-dipole turnstile antenna** specifically engineered for 2-meter Amateur Radio Direction Finding (ARDF) events. The author, WB6RDV, details a robust, omnidirectional, horizontally-polarized antenna, addressing the international ARDF rules requiring such characteristics at a height of two to three meters above ground. This contrasts with the vertical polarization often used in Southern California, highlighting the design's adherence to specific event requirements. The electrical design employs a classic crossed-dipole with a 75-ohm phasing section, resulting in a slight impedance mismatch and an SWR of approximately 1.3:1 with a 50-ohm feedline. Construction utilizes readily available and inexpensive PVC plumbing components and 1/8-inch bronze welding rod for elements. The guide provides step-by-step instructions for mechanical assembly, including drilling element holes at precise 90-degree spacing and preparing the RG-179 matching section. WB6RDV shares insights from his own build experience, discussing the use of plated brass versus aluminum spacers for element attachment and the effectiveness of crimping as an alternative to soldering. The document also covers final assembly, including the integration of ferrite beads as a choke balun and options for weatherproofing and alternative mounting configurations, emphasizing the adaptability of the design for other VHF bands through scaling.

Fox hunting site with details of a PC based DF system

A home made yagi antenna featuring 6db forward gain and 22 Db front back

VectorFox is a software born to incorporate a PC into the fox hunting environment. VectorFox is able to take inputs from up to 5 sources, such as a 2m beam, a 2m signal meter, a TDOA, etc, and display the results on the screen. VectorFox also accepts Agrelo inputs. From these results the operator can choose which indication is best and have a line drawn on the map in the direction of the signal.

For amateur radio operators engaged in **radio direction finding** (RDF) and **transmitter hunting** (T-hunting) activities, this resource provides a catalog of printed circuit boards (PCBs) for constructing various DF and foxhunt-related projects. The offerings include PCBs for 80-meter fox transmitters and receivers, UHF fox transmitters with audio recording capabilities, and several designs for general-purpose radio direction finders. Specific projects like the "Simple 80M ATX-80 Transmitter" and the "N0GSG DSP Radio Direction Finder" are listed, along with attenuator boxes and specialized components for Doppler DF systems. The catalog details PCBs for projects published in prominent amateur radio magazines such as *73's*, *CQ*, *QST*, and *PE*, indicating their origin and design pedigree. For instance, the "Montreal Fox Controller" is sourced from the *Homing-In* column by Joe Moell, K0OV. The resource also lists components for advanced Doppler DF systems, including main boards, LED display boards, and antenna switch boards, with options for programmed PIC microcontrollers. Pricing for each PCB is provided, allowing hams to acquire the necessary components for their DIY RDF endeavors.

Schematic anc PCB for a fox hunting receiver for 80 meters band

Hidden transmitter hunting, often called fox hunting or Amateur Radio Direction Finding (_ARDF_), presents a unique challenge for radio amateurs. This resource details the _PicCon_ controller, a specialized device designed to automate the transmission of signals for such events. It integrates with a standard radio transceiver, functioning similarly to a packet radio TNC, by controlling the Push-To-Talk (PTT) line and injecting audio tones or modulated CW Morse code into the microphone input. The _PicCon_ unit is field-programmable using DTMF tones received via the radio, storing all settings in EEPROM for power-off retention. Its compact design and low power consumption (a few milliamps from a 7-35VDC source) make it suitable for remote deployment. An onboard LED indicates operational status, and a push-button allows manual start/stop of transmissions without DTMF. Typically supplied as a kit, _PicCon_ includes a PCB, components, and a comprehensive manual (available in HTML, RTF, and PDF formats). The kit provides a six-conductor interface cable, but users must supply radio and power plugs due to varied configurations. Byon, _N6BG_, developed this controller, which is available from the Byonics website.

Building the WB2HOL foxhunting beam antenna

The 2 metre fox-or transmitter is a small low power transmitter which mounts in a small plasic pipe and runs off two AA batteries. The board measures just 12mm by 70mm.

Two-meter and aircraft band receiver specifically designed for RDF on foot, sold by Bryan Ackerly VK3YNG

Construction of attenuator, suitable for fox hunts at 144mhz

An Offset Attenuator for fox hunts.

Newest ARRL westcoast convention. Features fox hunt, banquet, speakers, VE testing, swapmeet, many prizes.

A full superhetrodyne SSB fox hunting receiver kit

The 80 metre fox-or/test transmitter is a small low power transmitter which is designed to be used as an alignment aid for running up 80 metre foxhunt or ARDF receivers. It is also usable as a micro transmitter for fox-or-ing events.

The Microsniffer is a fully autoranging VHF or UHF sniffer which has been designed for those who are foxhunting on a budget.

Using APRS For Direction Finding

A 7 dB directional gain is reported for this portable VHF Yagi antenna design, which utilizes cut metal tape measure sections for its elements. The resource details the construction process for a 2-meter band antenna, emphasizing its ease of build and portability. It specifically mentions the design's suitability for radio direction finding (RDF), fox hunting, and communication with satellites and the International Space Station (ISS), highlighting its practical applications for amateur radio operators. The construction cost is estimated at under $20, with potential for even lower expense if salvaged materials like old tape measures and PVC pipes are used. The article references _Joe Leggio's_ (WB2HOL) original design, noting specific alterations made by the author. It also compares this design to other DIY Yagi antennas, including _FN64's_ 2-meter band and _manuka's_ 70-cm band tape measure Yagis, underscoring its unique combination of simplicity, portability, and effective performance with a 1:1 SWR achievable on the 2-meter band.

A Tape Measure Beam Antenna for Radio Direction Finding based on WB2HOL design.

This processor controlled autoranging sniffer has become popular for vehicle based foxhunting in Australia

website of the Balloon Fox Hunting on 80 and 2 meters. Before well known as the Dutch Balloon Fox Hunting or the Hobbyscoop-hunt

Details the Big Thunder Amateur Radio Club (BTARC), a long-standing amateur radio organization based in Boone County, Illinois, established in 1962. It covers the club's mission to enhance the skills of local hams, promote radio knowledge, and foster social interaction among operators. The resource outlines BTARC's commitment to community service, including emergency communications support through RACES, and its active participation in events like Field Day, fox hunts, and public service communications for local races. Explains the club's history, including the establishment of its first repeater in the 1970s by members WD9JGH, Mike George, K9ORU, and Claude Horsman, WB9PMM, using a VHF Engineering kit and a Sinclair duplexer. It provides specifications for two club-maintained FM repeaters: a 2-meter repeater on 147.375 MHz (+600 KHz shift, 100.0 Hz PL tone) and a 70-cm repeater on 442.825 MHz (+5 MHz shift, 114.8 Hz PL tone). The club hosts a weekly 2-meter net on Sundays at 7:00 PM local time and holds monthly meetings on the second Thursday at the Spring Township Building in Belvidere, IL.

A home made RDF 3 elements Yagi that can be used for fox hunting. The particularity of this antenna is that it can be folded, in order to save space while travelling. In Dutch.

If your club holds only two-meter ARDF events, you are missing half the fun. There is another international foxhunting band, too.

RDF Equipment Ideas for VHF Foxhunting and Radio-Orienteering. This information is primarily for the Amateur Radio two-meter band

The Peilgruppe Neandertal, featured on Peilsport.de, actively promotes _Amateur Radio Direction Finding_ (ARDF), also known as fox hunting. This German group combines radio technology with outdoor sport, participating in regional and national ARDF events. Members access current ARDF schedules, competition results, and downloadable certificates directly from the site. The content highlights the adventurous spirit of ARDF, emphasizing the blend of technical skill and nature exploration. DL7ET and DR9P are noted callsigns associated with the group, indicating active participation from experienced operators. The site also covers related activities like Foxoring, a variation of ARDF that integrates orienteering with radio direction finding. This resource serves as a central hub for the Neandertal group's activities, documenting their involvement in a sport that challenges both physical endurance and radio proficiency.

The RDF 10 second fold-out Yagi especially for fox hunting. have more fun stuff on this page. PD0G

The Loudoun Amateur Radio Group (LARG) of Loudoun County, Northern Virginia, was founded in July 1993. LARG is a family oriented club with a wide variety of activities and interests. Some of these activities include public service, emergency communications support, high altitude balloon radio, camera and video flights, fox hunts, contesting and radio sport DX-ing

The Pikes Peak Radio Amateur Association (PPRAA) serves as an ARRL Special Service Club, providing a calendar of events and activities for its members and the wider amateur radio community. The resource details upcoming events such as the USS Pueblo Memorial Museum Ships Weekend activations, a Cubical Quad Antenna Workshop, LARCFest, and various hamfests including Dayton Hamvention and Duke City Hamfest. It also lists on-air activities like a FreeDV digital voice mode event on 10 meters, a Black Friday Simplex Event on 2M and 70cm, and a 10m event for Technician class operators, emphasizing SSB privileges from 28.300 to 28.500 MHz. The PPRAA's event schedule includes educational opportunities like a Technician Class and a Soldering Workshop, alongside social gatherings such as the PPRAA Picnic and Car Show. Past event summaries highlight successful activities like the 2024 Megafest Raffle, Winter Field Day, and multiple fox hunts utilizing frequencies like 147.420, 147.480, and 147.540 MHz. The club actively supports POTA activations, exemplified by their AF0S park activation at Cheyenne Mountain State Park, and participates in historical commemorations like the USS Pueblo Memorial operations, demonstrating a broad engagement across various amateur radio facets.

Explore the world of fox hunting with the Fox Hunt V7 Kits and Assembled Units. Learn about the different antennas used for fox hunting, such as the tape measure beam with an offset attenuator. Discover how to make your own WB2HOL beam antenna using PVC pipe, T's, and a tape measure. Find out how the offset attenuator works and how it can help you track down jammers and interference. Whether you're a seasoned fox hunter or just starting out, this page offers valuable insights and tips for improving your hunting skills.

Details the construction and performance of a phase-controlled receiving array, specifically a **MicroSWA** variant, optimized for QRP low band fox hunting on 40M and 80M. The resource documents the author's iterative design process, addressing significant regional noise challenges encountered during 0100-0230 UTC fox hunt periods. Initial experiments involved a director wire on a 40M vertical, yielding limited improvement, prompting a shift towards advanced null-steering techniques. The project leverages concepts from Victor Misek’s "The Beverage Antenna Handbook" and Dallas Lankford’s extensive work on phased receiving antennas for urban lots. A key modification involved integrating a new passive phase control box and a push-pull **Norton common base preamp** using 2N5109 transistors, designed for high third-order intercept performance to maintain weak signal integrity amidst strong adjacent signals. The system incorporates Faraday-shielded transformers with RG174 primaries on -75 ferrite cores, housed in ABS plastic pipe. Performance tests confirmed the MicroSWA's ability to produce deep, steerable nulls, achieving approximately 30 dB noise reduction on 160M, 80M, and 40M. This enabled detection of QRP signals undetectable on conventional transmit antennas. The final unit includes front panel controls, a 10-11 dB preamp, and a robust power conditioner, demonstrating effective noise mitigation for challenging low band QRP operations.

Raspberry pi powered fox hunt transmitter. pifox is a script written by KM4EFP to configure, control, and deploy a Raspberry Pi as a fox hunt transmitter. No external radio needed use your Pi's gpio output as a radio transmitter.

Fox Hunting for Scouts. Jamboree can be an opportunity to promote ARDF among Scouts all around the world.

This article describes a DIY RF field strength meter project inspired by VK3YE's "The Squeakie" design. The device, built around a 555 timer IC and a 1N4148 diode, converts RF signal strength into audible tones with proportional pitch. The author enhanced the original design by adding volume control, LED indication, and digital readout capabilities using an Arduino Nano and LCD display. The completed project functions as a versatile RF detection tool, suitable for antenna testing and fox hunting, while offering multiple output methods: audio, visual, and digital measurement display.