Links for RDF, T-hunting, and Radio-Orienteering
Mobile T-Hunting
Find out how to get involved in mobile T-hunts in your area of the USA by
visiting these local T-hunt Web sites. (Listings are alphabetical by
state and city.)
- Anderson, CA, near
Redding
- Chico,
CA
- Fremont, CA and the
South San Francisco Bay area
- Los Angeles, CA area
Saturday night and All-Day hunts
- Lancaster, CA
and the Antelope Valley
- Mission Viejo,
CA and the rest of southern Orange County
- Montclair/Upland/Alta Loma, CA area by Inland ARS
- Napa, CA
- Sacramento,
CA
- San Diego, CA area including La Mesa and El Cajon Site 1 and Site 2
- Santa Barbara, CA, by SBARC; also WB6RDV's site has a
complete southern California hunt list
- Santa Clarita, CA
- Stockton, CA and the
California Central Valley
- Thousand Oaks,
CA, also Ventura, Oxnard, Camarillo and southern Ventura County
- Yolo, CA
- Colorado Springs,
CO
- Denver, CO, also
Loveland
- Wallingford,
CT
- Broward,
FL Flamingo Net
- Daytona Beach, FL
- Mims, FL and north Brevard County
- Palm Beach, FL
- Chicago, IL
and suburbs hunt schedule, also Chicago FM
Club hunt page
- Kankakee, IL
- Lexington,
KY
- Brockton,
MA
- Pittsfield, MA and
northern Berkshire area
- Baltimore,
MD
- Jonesville, MI and Hillsdale County
- Lansing, MI
- Kearney,
NE
- Lincoln,
NE
- Trenton, NJ and the
Delaware Valley
- Albuquerque,
NM
- Hudson river valley,
NY
- Columbus, OH
- Lake County, OH
- Middletown,
OH
- Lehighton/Weissport, PA
- Pottstown, PA, including Berks, Chester and Montgomery
Counties
- Austin, TX
- Houston, TX
- Salt
Lake City, UT
- Chesapeake,
VA
- Staunton,
VA
- Bellingham and Whatcom
County, WA and Bremerton area
- Pullman,
WA
- Seattle, WA and
Puget Sound area
- Superior, WI and Duluth, MN
Some localities have regular (or occasional) T-hunts,
but no Web coverage of them. Find out about hunts in the areas below by sending
e-mail to the local Homing In Correspondent
(Listings are alphabetical by state and city. E-mail addresses have been
obscured to foil spammers. Replace "-at-" with "@" when addressing your
e-mail.):
- South Windsor, CT via Art Grondine N1WSM (drwho-at-ntplx.net),
including Hartford area
- Dover, DE via Sam Guccione K3BY (sguccion-at-outland.dtcc.edu),
also Virginia/Maryland peninsula
- Titusville, FL via Bud Hughes K4CWG (bhughes-at-expedient.com)
- Atlanta, GA via Jim Sorenson KA4IIA (ka4iia-at-radio.org)
- Honolulu, HI via Russell Houlton WH7O (r_houlton-at-compuserve.com)
- Indianapolis, IN via Clifford Vaught N9FHF (foxhunt-at-in.net)
- South Bend, IN via Myer Blatt N9OCA (n9oca-at-aol.com)
- Boston, MA via Minute Man Repeater Association (mmra-at-mmra.org)
- St. Louis, MO via Mike Musick NØQBF (mike-at-pocketaprs.com)
- Tupelo, MS via Jack Smith KE4LWT (ke4lwt-at-arrl.net)
- Doylestown, OH via Silver Creek Amateur Radio Association
(w8wky-at-amsat.org), including Akron/Canton area
- Shelby County, OH via Dale Kubichek N6JSX (n6jsx-at-yahoo.com)
- Toledo, OH via Vince Vassello KB8TEP (kb8tep-at-arrl.net)
- Oklahoma City, OK via Charlie Shelden KC5NBH
(shelden3-at-ionet.net)
- Locust Grove, OK area via Rich Conn KD5JXU
(yonkersmtham-at-chouteautel.com)
- Portland, OR via Dale Hunt WB6BYU (wb6byu-at-arrl.net), also Salem,
OR and Vancouver, WA
- Harrisburg, PA via Dale Snyder N3KXC
(dsnyder-at-postoffice.ptd.net), also Reading and Lancaster
- Milwaukee, WI via Paul Gruettner WB9ODQ
(PGruettner-at-hga.com)
Non-commercial Web sites regarding technical RDF topics have been
posted by these individuals and groups (alphabetical by last name):
- Dennis
Boehler KF4TJI -- VHF antennas for club projects
- Jacques
Brodeur VE2EMM -- PIC Microcontroller projects for RDF including foxboxes
and dopplers, also see remarks on the doppler projects at Utah
Amateur Radio Club site
- Rick Ching
KH7O -- HB9CV-type two-element array for two meters, other projects
- David Deane
G3ZOI -- Two-meter AM ARDF receiver, turnstile antennas
- Brian DeYoung K4BRI
-- Polar bearing display hardware and software for PCs and PDAs
- Peter Fraser VK3ZPF
-- Vector Fox, Rotor Hunter and TM742 mods
- Randy Holland
KO6KC -- Mounting for mobile 2m quad
- Paul
Jaruszewski KD6LOR -- Antenna position encoder
- Kevin Kelly N6QAB --
RDF devices for mobile and on-foot
- Peter Kerckhoff KBØYRQ -- Rocket recovery RDF on 70cm
band
- Tony Levand AA9CC -- Receiver hunting and airplane
bounces
- Joe Leggio WB2HOL -- Projects: Foxbox, attenuators, beam,
TDOA set
- Harry Lythall SMØVPO -- Commutated antenna DF
- Mario
Sacco LU6DPP -- Doppler page from Argentina
- Charles Scharlau NZØI -- Collapsible quad and active
attenuator
- Bob Simmons
WB6EYV -- A mini-transmitter, Doppler projects, APRS interface, and
computer bearing readouts with electronic compass for PCs and PDAs
- Ken Swaggart W7KKE -- Pico-Doppler RDF software and rooftop
antenna
- Utah
Amateur Radio Club -- TDOA sets by Mike Mladejovsky WA7ARK
- Greg
?? VK3VT -- Mobile RDF beam from Australia
Mobile T-hunting is not limited to the USA. Here are some other places
around the world where it is done:
- Adelaide,
Australia Web site by VK5ZCF
- Canberra,
Australia Web site by VK1KNP
- Urunga,
Australia Web site about Urunga Convention on Easter weekend with
foxhunts
- Belgium by
ON5NV (in Flemish)
- Barry, Ontario,
Canada Web site
- Belleville,
Ontario, Canada Web site
- York/Newmarket region, Ontario, Canada Web site
- Peterborough, Ontario,
Canada Web site
- Montreal, Quebec, Canada Web site by VE2EMM
- Basingstoke,
England Web site by Basingstoke Amateur Radio Club
- Nottingham,
England Web site by AR Club of Nottingham
- Bangalore, India Web page
- Annual
Balloon Foxhunt in Netherlands on 2 and 80 Meters
- Portugal by
AMRAD-Portugal (in Portuguese)
- Portugal by CT2IZV (in Portuguese)
- Spain by
EA7BDD (in Spanish)
- 160 Meter Band in
UK
On-Foot Foxhunting
On-foot foxhunting (also called foxtailing,
radio-orienteering and ARDF) is growing rapidly in the USA. In addition to southern California ARDF
events and upcoming
championship news at this site, see these sites for information on
stateside ARDF activities:
Santa
Barbara Amateur Radio Club, host of the Fourth USA ARDF
Championships in 2004 and the Seventh USA ARDF Championships in 2007
Piedmont
Transmitter Tracking in Raleigh/Durham area, host of the Sixth USA ARDF
Championships in 2006
offcycle.org based in
Cincinnati
Texas ARDF in
Houston and Austin area
USA
Radio-Orienteering Group (USA-ROG) in San Francisco Bay area
Here are e-mail contacts for radio-orienteering leaders in other parts
of the USA and Canada (Listings are alphabetical by state/province/city. E-mail
addresses have been obscured to foil spammers. Replace "-at-" with "@" when
addressing your e-mail.):
- Victoria, BC via Joe Young VE7BFK (ve7bfk-at-rac.ca), ARDF
Coordinator for Canada (RAC)
- Los Angeles and Orange County, CA via Joe Moell KØOV
(k0ov-at-homingin.com), ARDF Coordinator for USA (ARRL)
- Pleasanton, CA via Bob Cooley KF6VSE (rccooley-at-comcast.net)
- Santa Barbara, CA via Marvin Johnston KE6HTS
(marvin-at-west.net)
- Denver, CO via Larry Benko WØQE (w0qe-at-bnk.com)
- Bozeman, MT via Harley Leach KI7XF (harley-at-ece.montana.edu)
- Portland, OR via Dale Hunt WB6BYU (wb6byu-at-arrl.net), ARDF
Coordinator for IARU Region 2 (North and South America)
- Montreal, QC via Jacques Brodeur VE2EMM
(ve2emm-at-qsl.net)
ARDF is the predominant style of RDF contesting outside the USA. There are
Web sites about it in many countries (in English unless otherwise
indicated).
Equipment Suppliers
Here are the past and present sellers of equipment
and software for RDF and related purposes to the Amateur Radio market, in
alphabetical order. A listing here does not imply an endorsement of products.
- Agrelo Engineering -- Agrelo's microtransmitter products and DFjr
doppler add-on for FM receivers are no longer available. The company is out of
business. SWS Security in Maryland, who took over production when Agrelo
Engineering folded, no longer supports the DFjr product line.
- Arrow Antenna --
Manufacturer of lightweight VHF/UHF yagis for mobile and on-foot RDF. Also
makes resistive attenuators for mobile T-hunting, active/offset
attenuators for on-foot RDF, and VHF/UHF RDF loop
antennas. Reviewed in Homing In for
August 1993 (yagis), July 1994 (resistive attenuator), April 2003 (loop) and
Winter 2006 (active attenuator).
- APRS
for DOS and APRS for
Windows/Mac/Linux -- Multi-purpose software for object tracking, RDF and
much more. Interfaces with GPS and RDF sets. Links tracking sites via packet
radio. Discussed in Homing In for October
1994, January 1995, February 1995, and August 1995. DOS and Mac versions have
the most RDF-related features. Unfortunately, PocketAPRS for Palm (which had
excellent RDF support) is no longer available.
- BMG Engineering, Inc. -- Former maker of SuperDF dual-antenna
phase-front (TDOA) add-on for FM receivers. Products are no longer available;
sales were suspended in October 1999. Reviews in Homing
In for November 1989 and the T-Hunt book.
- Byonics -- Miniature
PIC devices by N6BG, including the PicCon transmitter controller. PicCon has modes for both
mobile T-hunts and synchronized MOE/MOI/MOS international foxhunts. It was
reviewed in Homing In for March 1997.
Byonics also sells the DSP-RDF Doppler direction finder kit by Dan Welch W6DFW.
- Cubex Quad Company --
Strung-wire VHF cubical quads for RDF. Reviewed in Homing In for February 1996 and plans for
dual-polarization version are in February 1997 issue. Since publication, Cubex
has changed owners and relocated to Florida. A second facility, Cubex ASC in Virginia,
makes dual-band (2m and 70cm) quads for OSCAR satellite communications, also
suitable for some RDF applications.
- Doppler Systems, Inc.
-- Doppler RDF add-ons for FM receivers featuring patented smooth-transition
switching. Reviewed in the T-Hunt book.
- Doppler DF
Instruments -- Bob Simmons WB6EYV sells kits, including the PicoDopp,
MiniAntenna, SquawkBox transmitter and Polar Plot for PDAs. SquawkBox reviewed
in Homing In for Spring 2005.
- FAR Circuits --
Circuit boards for the Roanoke
Doppler, Montreal Fox
Controller, Doppler-to-RS232
Interface, 80-meter ARDF
transmitter and many other home construction projects.
- Hamtronics,
Incorporated -- Supplier of ham radio kits, including low-power VHF/UHF
transmitters suitable for foxboxes. T301-2Y synthesized exciter reviewed in
Homing In for August 1998.
- Happy Flyers -- California organization that sold kits for an
amplitude-comparison VHF RDF set for aircraft ELT location, as described in
the T-Hunt book.
This organization has disbanded and kits are no longer available.
- L-Tronics
-- Long-time provider of "Little L-Per" RDF sets for airborne, vehicular and
on-foot search/rescue. The original crystal-controlled L-per is no longer made
nor sold by L-Tronics, but pre-owned units may be available from upgrading
owners. Many hams have added appropriate crystals to original L-Pers for use
on VHF and UHF Amateur Radio bands. A newly designed synthesized L-Per with
wide frequency coverage became available from L-Tronics in January 2006.
- Marvin Johnston
KE6HTS -- Supplier of kits and circuit boards for RDF projects including
the KØOV Offset
Attenuator, the WB6BYU 80-meter ARDF
receiver-antenna set, the WB6EYV two-meter
50 mW "MicroHunt" ARDF transmitter and the WB2HOL tape
measure two-meter Yagi.
- Motron Electronics --
Software/hardware for "fingerprinting" and "signature analysis" of received
signals. Reviewed in Homing In for November
1994.
- National RF,
Incorporated (formerly Radio Engineers) -- Makes "Vector-Finder" hand-held
phase-front (TDOA) add-on units for VHF ham radio and marine use, plus
resistive attenuators and portable 2-meter quads. The Vector Finder was
reviewed in Homing In for July 1996.
- North Olmsted
Amateur Radio Depot (NOARD) -- Supplier of kits for the HANDI-Finder®, a
simple dual-antenna RDF add-on. See "Sense The Right Way To
Go With The HANDI-Finder" at this site for performance improvements.
- OK2BWN
Radio Sports Equipment -- ARDF transmitters and receivers for 80m and 2m
bands by Jiri Maracek OK2BWN in Czech Republic.
- Optoelectronics -- Frequency counters and "bug busters" for
sniffing signals on foot. Discussed in Homing
In for July 1990; R20 reviewed in February 1994.
- Ramsey
Electronics -- "SlyFox" transmitter and "Foxhound" phase-front (TDOA)
add-on for FM receivers. Reviewed in Homing
In for December 1993 and August 1994. See design improvements for
these units at this Homing In site.
- Rolcon RF Systems --
VHF and UHF yagi antennas covering many frequency ranges from 50 to 970 MHz.
- Ron Graham
Electronics -- Receivers and sniffing antennas for on-foot RDF on 80 and 2
meter bands from VK4BRG in Australia. Reviewed in Homing In for December 1997.
- Sniffer4 -- Tiny synthesized two-meter and aircraft band
receiver specifically designed for RDF on foot, sold by Bryan Ackerly VK3YNG
in Australia. Reviewed in Homing In for
April 2003. An 80-meter ARDF receiver/antenna unit is also available from
Bryan.
- Steven.Makes.It -- Circuit boards for the Roanoke
Doppler. Also sells a clone of the the HANDI-Finder® (see NOARD above).
- Swiech
Communications Systems -- Rugged black-anodized VHF yagis for "stealthy"
nighttime T-hunting.
Also see my Hardware Sources page
for links to suppliers of circuit boards, special parts, and complete kits for
RDF-related home construction projects.
Sophisticated RDF equipment and radiolocation systems and services are
advertised by the following companies to the government and military
markets, as well as to law enforcement and industry. As before, a listing
does not imply my endorsement, or even the availability of actual products.
- Astron Wireless
Technologies in Sterling, VA
- Caravan
International Corporation in Rio de Janeiro, Brazil
- CEA Technologies
(Warrlock Direction Finding) in Canberra, Australia
- Cellular
Technology Engineering and Consulting in Munich, Germany
- CSE Associates
Incorporated in Walkersville, MD
- Cubic Corporation
(formerly OAR) in San Diego, CA
- Direction
Technology, Incorporated in Centreville, VA
- DRS Codem Systems in
Merrimack, NH
- EDO Corporation
(formerly Condor Systems) with headquarters in New York City
- Falcon-Protec
PLC in Gloucestershire, England
- Fernau Avionics Limited
in Bedfordshire, UK
- General Dynamics C4
Systems in Scottsdale, AZ
- Granite Island Group near
Boston, MA
- Interferometrics
Incorporated in Chantilly, VA
- Jenkins Engineering and
Defence Systems, Ltd. in Matraville, NSW, Australia
- L3 Communications in
New York City
- QinetiQ Ltd in
Hampshire, UK
- Monteria LLC in Mt
Airy, MD
- Poynting Antennas
Ltd in Wendywood, South Africa
- Radio Reconnaissance
Technologies in Stafford, VA
- RDF Products in
Vancouver, WA
- RF Engines on Isle of
Wight, United Kingdom
- Rockwell-Collins (Avionics) in Cedar Rapids, IA
- Rohde and
Schwarz in Munich, Germany
- Servo Corporation
of America in Westbury, NY
- Southwest
Research Institute in San Antonio, TX
- Spectrum Signal
Processing, Inc in Burnaby, BC, Canada
- Summitek
Instruments in Englewood, CO
- SWS Security in Street,
MD
- Synectics Surveillance Technology in Tewkesbury, England
- Technology
for Communications International (TCI) in Sunnyvale, CA
- Taiyo Musen Company in Tokyo, Japan
- Tecom Industries,
Inc in Thousand Oaks, CA
- Thales Communications in Gennevilliers, France
- Titan Systems
Corporation, Signal Products Division
- Tracking
Products in the Denver area
- WiNRADiO
Communications, division of Rosetta Laboratories, Oakleigh, Australia
- Zeta, a unit of
Integrated Defense Technologies in San Jose, CA
Specialized transmitters and RDF tracking equipment for
wildlife management (and sometimes for pet and human tracking) are
advertised by these companies. Same disclaimer applies. For more on research
uses of RDF, see Homing In for July 1995,
January 2003, and Summer 2005. Also see the T-Hunt book.
- AVM Instrument
Company in Colfax, CA
- Care Trak in
Carbondale, IL
- Communications
Specialists in Orange, CA, for wildlife, also for cats, for dogs, for model aircraft, and
for law enforcement
- Environmental
Studies in Goettingen, Germany
- Grintek
Telecom in Centurion, South Africa
- Global Tracking
Systems in Sylvan Lake, Alberta, Canada
- H.A.B.I.T. Research
Ltd in Victoria, Canada
- Holohil Systems in
Carp, Ontario, Canada
- Information
Unlimited in Amherst, NH
- Locator Systems
Corporation in Victoria, BC Canada
- Lotek Engineering in
Newmarket, Ontario, Canada
- Magnum
Telemetry in Grifton, NC
- Marshall Radio
Telemetry in North Salt Lake City, UT
- Quick Track in
Dothan, AL
- Sirtrack Limited in Havelock North, New Zealand
- Telonics in Mesa,
AZ
- Televilt Positioning
AB in Lindesberg, Sweden
- Titley Electronics
in Ballina, Australia
- Tracker Radio
Location Systems in Springdale, AR
- TracMe Beacons in
Victoria, Australia
- Wildlife
Materials, Incorporated in Carbondale,IL
- Wildlife Track
Incorporated in Livermore, CA
RDF is an important tool for search and rescue. Here are
some sites with information about it:
- Artex Aircraft Supplies of
Canby, OR, maker of Emergency Locator Transmitters (ELTs)
- Becker Avionics
Systems of Rheinmünster, Germany, makes emergency beacons and airborne
tracking sets
- Front Range Electronic
Direction Finders, Inc (Colorado), a search/rescue group
- L-Tronics in
Santa Barbara, CA, makes well-known L-Per® RDF sets for tracking ELTs
- Narco Avionics of
Ft. Washington, PA, maker of ELTs
- Seimac in Bedford, Nova
Scotia, Canada makes locator beacons and the ProFIND RDF set
- Tracker Locating Systems of
Finland, maker of ELT tracking equipment
To list your site or become a Homing In
Correspondent for your area, send e-mail to [email protected].
Surfing suggestion: Is it necessary to build or buy a doppler set to
be competitive on hidden transmitter hunts? Find out what southern California
winners use at my Let's
Go T-Hunting page.
Back to the Homing In home page
This page updated 10 May 2007