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Amateur Radio Direction Finding (international abbreviation ARDF, in Czech ROB - "radiovy orientacni beh") came into being a couple of decades ago as a sideline amateur-radio pursuit known as fox-hunting and today it constitutes an entire sport, with fixed rules, an elaborately drawn-up competition system and of course with the need for regular training without which few would make it to international level.

What does this sport involve? The basic idea is to seek out a set number of transmitters (control points) with the aid of a radio receiver and a map (orienteering maps are used) in the best possible order (this is not definitely fixed and is subject to the decision of the competitor) and to run to the finish line in the shortest possible time. On the map the competitor has just the start and the finish marked in (or to be more precise the position of the finish-line beacon transmitter transmitting constantly on a frequency slightly different to the competition frequency), otherwise everything depends on his or her work with the receiver, ability to find directions exactly, and of course fast running. The map is nothing more (or less) than an appropriate aid for the competitor to choose the best way between individual control points and then to the finish line.

The competition band is double: 3.5 MHz (80 m) and 144 MHz (2m). For receiver handling, the more complex "80" is in fact easier (using a ferrite antenna you first have to find a direction and then with a whip antenna the signal orientation) - the signal spreads out evenly (at least in non-mountainous Czech conditions) and finding directions does not usually present too many problems even for beginners whereas the apparently simpler "2m" (requiring just one direct reading) has its drawbacks in the way the signal spreads over articulated terrain - weaker (to zero) audibility behind a hill, diffraction along contour lines, reflections from opposite or adjacent slopes - so that in this band it takes technical ability and above all experience of competitions more than just running and map-reading skills.

In contrast to traditional orienteering where around a hundred control points are set out in forests and there can be thirty odd ones on individual routes, radio orienteering makes do with a mere five control points. This is necessitated by the method of transmission - all the transmitters transmit on the same frequency at five-minute intervals and each one transmits during its allotted minute (no. 1 in the first minute, no. 2 in the second etc.) and then goes silent for the remaining 4 minutes so the competitor has to try to run to a specific transmitter within one minute and if he or she is to far away then to at least find its direction exactly and thus to find it without the signal (or to wait for four minutes). Under international rules the full complement of five transmitters is sought by men and the other category, women, for juniors and veterans they always leave one out.

If a novice category competition runs together with adults then the former normally have two or three control points; if the novices are running in an independent competition (or as the case may be, at the same time on a different band) then they have more transmitters on the route (five for the oldest novices) at smaller distances of course. The latest generation of transmitters the size of a small brick have frequencies and transmission lengths available by means of simple switching, which has given rise in the last few years to the increasing promotion of competitions involving shortened (half) transmissions at least here on our native soil.

has been able to boast a number of significant successes over the last twenty years. Whereas we did not have any marked success with the European Championships in the sixties and seventies, the very first world championship in 1980 went to Mojmir Sukenik, OK2UMO, who repeated his success four years later. The world championship contest in 1986 brought a silver and a bronze to Teringl, OK1DRT, and Simacek, and Petr Kopor's championship title two years later was the first of a long run of championship titles lasting to this day, from which our champions have always brought back at least one gold medal.

In 1990, the world championships were hosted by the former Czechoslovakia, in the High Tatras, and saw the rise of the upcoming Vit Pospisil. His gold and bronze came together with another bronze for the old-timer Blomann. At the following championships, the sixth, the juniors shone for the first time - Kejmar's gold came on top of another two medals for Hrazdil. We also came away with Pospisil's silver for the men and the first women's medal, a bronze for Dana Mejstrikova.

1993 saw the rebirth of the European championships, which were staged for the second time (the first being in 1967) by the Czech Republic in Milovy. A string of successes was scored by YL Jitka Simackova, with a gold, Pospisil again with a silver and then by Hanak among the men, Kejmar among the juniors and for the first time among the old-timers, Sukenik, OK2UMO.

The performance of the Czech youth in 94 came like a thunderbolt - Pavla Baierova's silver was even bettered by the gold won by Lenka Novotna, who at 15 was the youngest world champion ever. Let us also mention for the sake of completeness the bronze won by Fucik in the men's and the two bronzes won in the juniors' by Skob, who improved on that by one place in the 1995 European championships but was still overshadowed by the gold and silver won by Petr Jelinek. After a year out, Pospisil came back onto the men's scene, again successfully, in second place just in front of Vanek, who made up for all that with his triumph in the second competition. Pospisil added another silver the following year when apart from the other silver won by Sukenik, OK2UMO, the central figures were the juniors: in addition to the bronzes won by Jelinek and Kotulan, Jakub Oma struck gold for the first time.

So now to burning present issues: last year's world championships in Germany saw another silver in the old-timers' category for upcoming Karel Javorka, OK2PY, but the stars this year are the Omas, with Jakub winning again in the juniors' and his 16-year old sister, Michaela, winning in the women's. In the men's, there was a silver for Fucik and in the second band for Baier, who was only beaten by, well, who other than Vít Pospisil, whose long run of returns from each world competition with at least one silver medal has no precedent in world ARDF.

The 1998 world championships are being hosted for the first time in 6 years by Hungary. Will our representatives follow up their successful results of previous years? Including the as yet unmentioned valuable medals in the team events, since 1992 they have never come back home with less than 10 medals!

To be readily understood, we speak here simply of the world and European championships. The organization responsible for ARDF on a worldwide basis is the IARU, the International Amateur Radio Union, which is the body that arranges what is called in full the IARU ARDF World Championships and the Region I. IARU ARDF Championships (the European Championships).

Friends of ARDF in the Czech Republic come together under which collaborates with the in domestic matters and under an agreement on international representation.

There is more on ARDF on the AROB web-page: http://www.ardf.cz

© Petr Hrouda, 1998