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EME, bouncing radio signals off the moon is a fascinating way
of operating for radio amateurs.
Before the introduction of the digital mode JT65 it was necessary
to use big antennas and high power to get contacts with other
amateurs via EME.
The typical size for an EME station that sucessfully can work
other stations of similar size in CW on 144 MHz is something like
4 yagis with a power of 1 kW.
With a really huge antenna, 32 long yagis or more, it is possible to work small stations that no one else except the owners of similar monster arrays can work. In the old days, before JT65, this was the driving force behind building very large antennas. They allowed contacts with "horizonters", small stations with normal equipment for terrestrial communication. They could hear the big stations, the beacons, on a single yagi with a barefoot standard transceiver and make contacts in CW via the moon with it. The sucess and joy in EME contesting with a huge antenna comes from the contacts with small stations. The beacon stations, W5UN, SM5FRH and a couple of others have been very important for the development of EME. A large fraction of EMEers discovered this mode of propagation by having a contact with one of them. Today the situation has changed. JT65 allows contacts at much lower signal levels. The stations who marginally could work SM5FRH or W5UN in CW now can work hundreds of different stations in JT65 There is no reason for small stations to work CW any more. To them JT65 is more satisfying and they are unlikely to participate in a CW only contest. As a consequence, a really huge antenna is no more a big advantage. The stations that work CW at all are strong enough to be loud on a much smaller antenna. Going from a good design with 8 X-yagis to a monster array like the one SM5FRH used in the past with 32 X-yagis would not make it possible to work more stations in a CW only contest. Small stations now have an alternative that is better suited to their equipment and few of them can be expected to participate in a CW only contest just to give points to two or three stations with monster antennas. Stations that work JT65 in a digital contest are likely to have at least one reasonable yagi and 100W. No monster antenna is needed to copy the signal from such a station. The only good reason to make an over-sized antenna is to win the biggest and highest status contest, the mixed contest of ARRL. Newcomers who have no experience in CW will hear the loud signals in the loudspeaker from the beacon stations and they may well become inspired to try CW themselves. Morse code is no longer mandatory for an amateur license in many countries and the only reason for this charming mode of operation to survive in the long run is that it is better than other modes in some situations. CW is fast and flexible. There is no need to use transmit periods of a fixed length when signals are good (when X-yagis are in use with a waterfall display.) In the early phase of a mixed contest a huge antenna can create a pileup of many strong CW stations and pick them one by one for fast and efficient contacts. I do not think a mode like JT65 can handle a pileup of 5 or more stations well, but in CW it is easy. There has been an argument that CW and digital contests should be separated in time. This separation has been done in the Dubus and in the ARI contest. Separating also the ARRL contest would be a bad idea because the probability that a modest size digital operator discovers CW then becomes very low and the chance that huge antennas will exist 10 years from now would decrease. The current ARRL rules allow one QSO in CW and one QSO in digital mode on each band. To me, that does not seem logical at all - why not allow a third QSO in SSB and a fourth one in RTTY etc. In my opinion, one QSO per band regardless of mode would be the best rule. It is up to the operator to choose the best mode for each contact. Surely the winner would make most of his contacts in JT65, but he would have to work CW also - otherwise someone else would become the winner.... The current rules promote CW contacts, but they also present a threat to QSO integrity. It seems to me that two stations who completed JT65 would find it optimum to continue immediately in CW and that means that the CW contact becomes a sked, not a random contact. To me the integrity of sked contacts is problematic, particularly when part of the dialog is made through some other channel (the previous JT65 QSO). (Message 1:"I am here. You know my S/N. I start right now to send something you already know") I do not like this to be encouraged by the contest rules. One way out could be to change to allow points for one contact each weekend with the same station provided that the mode is different. Any station who is capable of working stations of his own size in JT65 is technically well enough equipped to be able to work CW with the biggest stations. In a mixed contest, a very large fraction of all participants have the equipment required to make several CW contacts. Those who get higher scores will be those who use this opportunity. By removing the digital and analog cathegories and having just one class for mixed, those who want to score well will have to use both modes. That in turn makes a really big antenna very valuable. To SM 5 BSZ Main Page |