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The site provides information on ARDF hardware to help the DF enthusiasts equip themselves for a 2m or 80m ARDF competition or even host an event.
Only simple receivers and QRP transmitters are required for ARDF, so home brewing equipment is economic, rewarding and productive.
All the designs and commercial products have been extensively field or event tested and more probably both!
Please contact for further details on the availability and pricing of the advertised items. This web site supports a non-commercial project, therefore supplies may be erratic!

2m ARDF Projects | click photos |
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| WB2HOL 3 element yagi
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| ROX-2T 2m integrated AM receiver using the TA7613AP (TDA1083)
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| 2m ARDF Transmitter
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| Turnstile Antenna
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Hard-To-Get Components
| from G3ZOI. Prices include p&p to EU unless shown otherwise |
ICS525-01R, User configurable clock multiplier.
Up to 50mW output at 145Mhz using a standard xtal. | 1 off £3.00, 5+ off £2.50 each | datasheet |
| TA7613AP (TDA1083) 1 chip AM/FM radio | £2.50 each | datasheet |
| TOKEN 10.7mHz filters | 20kHz-£2.00 each, 110kHz-£1.00 each, 150kHz-£1.00 each | datasheet |

On-foot ARDF, sometimes known as Radio-'O', has been popular in many countries for many years, particularly in Central and Eastern Europe. The more formal competitions, at both national and international level, conform to rules set by the International Amateur Radio Union (IARU).
It is a combination of Radio direction finding and orienteering.
Five beacons are hidden in a wooded site and transmit for one minute, in sequence,
on the same frequency. A unique call sign identifies each transmitter. The objective is to work out their locations from radio bearings, devise a route plan and then visit them,
on foot, as quickly as possible.
Each competitor has a receiver and a compass and is given an individual start time.
At, or near, the time of the departure, the organizer will issue a map (1/10000 or 1/15000) showing only the course start and finish.
A control card is also issued, and must be marked with a pin ( or electronic) punch
at each transmitter location as proof of discovery.
Each transmitter will be co-located with an orange coloured orienteering flag.
The competitor, using his/her receiver, will try to identify
the location the various beacons, by taking bearings and optionally plotting them on a map.
Your radio bearings may initially be ambiguous and you will need to refine your route plan as you progressively uncover the location of the controls.
Some will follow bearing directly, others prefer to circumvent
obstacles by map reading, and then use well marked paths... it is all is matter of strategy.
A popular 'handy cap' format in the UK is to specify a different number of transmitters to find, (from 3 up to 5), for various age group but with a single results list.
The winner will be the one who finds their quota of foxes in the shortest time.
In larger international ARDF events these age categories will be kept separate.
On average, the event is limited to 120 minutes. Penalties for going over the limit are very severe. If you do over-time you will be ranked by time alone, regardless of the number of transmitters found !
International events usually take place over two days.
One day using 2 meters (144MHz), the other day using the 80 meters band (3,5MHz)
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2m Events in Region 1 continue to use AM for the MCW Morse code signature, in contrast to 'new world' regions, where FM has been adopted, due to the popular of the FM-handy.
Why stick with AM? It's primarily a legacy from the long establishment of ARDF in Region-1, but staying with AM has advantages.
Simple manually controlled AM receivers, without AGC, make very good DF receivers. i.e. the volume of the received signal is relative to the signal strength.
The availability of simple cheap receivers which are intuitive helps to keep the 'sport' open for beginners, youth and non-amateurs.
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The logistics of organizing an ARDF event are much more demanding than a club 2m foxhunt. You will almost certainly need help to assemble all the equipment and need participants from outside your club to make it worthwhile.
Planning an ARDF event shares a lot in common with traditional orienteering.
Establishing contact with your local Orienteering Club, is very highly recommended. Orienteering Clubs will have maps and knowledge of suitable venues. In addition orienteers with a passing interest in technology or Amateur Radio are often good candidates for new ARDF recruits!
Most Orienteering events are open to all, with 'colour coded' courses for a wide range of ages and abilities. Just going an event and seeing the organization, will prove to be a valuable experience. If you feel a little more adventurous, take a compass with you and try a beginners 'Orange' course for a taster !
See the British Orienteering Federation web site for more information.
Please let the existing UK ARDF community know of your ARDF activities so, they can coordinate a national events calendar.
See the RSGB Amateur Radio Direction Finding Committee Site for more information.
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