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Field Day was a great success again this year. CVARC operators made 1020 contacts, working 45 of the 50 States. The only states not worked where Maine, Vermont, Connecticut, Delaware, and Alaska. In addition, the Canadian Provinces of British Columbia, Alberta, Saskatchewan, Ontario, and the Maritime Provinces were worked along with Mexico and Cuba.
Under Field Day rules, each station contacted was required to identify itself by its call sign, the number of transmitters operating at its site, the classification of its site, and the ARRL/RAC Section where its site was located. For example, we were identified as AA6CV 11A SB, since we were all using the CVARC club call sign (AA6CV), we had 11 transmitters operating at our Field Day site, we were a field site with more than 3 people, and we were located in the Santa Barbara (SB) ARRL Section. Our field day summary sheet below shows the number of contacts made by each of our stations. Also shown are the classes of sites that we worked. 68.4% of the sites were Class A, like ourselves. In comparison, there were relatively few of the remaining classes. The next largest class was home stations working off of commercial power at 13.8%. The new Emergency Operation Center class made up 6.6% of the stations that we contacted. The number of stations (transmitters) at each site that we worked is also shown on the summary page. Most of the sites had 1 or 2 stations operating. Our site with 11 stations was one of the very few large sites. The largest site that we worked was a Maryland site with 37 stations.
Following the summary charts, and continuing through the newsletter, are charts showing the number of contacts made by each of our stations and the ARRL/RAC Sections where the stations that they contacted were located. The list of ARRL/RAC Section Abbreviations is also shown below. The left hand edge of each chart begins with the contacts made in our own Santa Barbara (SB) Section. The contacts are progressively further away as you move to the right. The most distant Sections contacted are on the right hand edge of each chart. The charts for all of our Field Day stations are shown except for the 20m CW station.
The 20m CW team of Greg, Alan, Mark, and Bruce worked 39 of the 50 states, 4 Canadian Provinces, and Cuba resulting in a chart that was too long to publish in this newsletter. However, with the large number of stations that they worked, it was relative easy to identify the hop distance of their signals. Their hop distance turned out to be approximately 430 miles per hop. When an HF signal leaves the antenna, it travels up into the Ionosphere, is refracted by the Ionosphere, and returns to Earth at some distance location. The distance from the antenna to the first distant location where the signal returns to Earth is the hop distance. The hop distance is determined by the altitude in the Ionosphere at which the refraction takes place and the angle, with respect to the ground, at which the signal leaves the antenna. The take-off angle is determined by the antenna’s height above ground measured in wavelengths. The 20m CW beam antenna was about ½ wavelength above the ground (about 30 feet up). At this height, the antenna should have a take-off angle of around 30 degrees. This angle, and refraction in the Ionosphere at about 125 miles up, would produce a skip distance of approximately 430 miles. On the 20m CW chart, the hop distance is marked by a high number of contacts in a particular location. The first 20m CW hop occurred in Arizona, the second in Colorado, third in South Texas, and fourth in Illinois. The arcs drawn though these locations containing a high number of contacts are spaced consistently at around 430 miles. The 20m CW hops beyond the fourth were less evident. The hop map for the 20m CW station is shown following the c.
The 40m SSB and CW teams saturated the west working all of the ARRL Sections from Santa Barbara out to Colorado, the boundary of the 40m range. Beyond this range, sporadic 40m contacts were made in the central and eastern United States. A 40m map is also shown on Page 9. 40m saturation of the west was primarily the result of Near Vertical Incident Skywave (NVIS) propagation resulting from the low (less that ¼ wavelength above the ground) inverted V antennas used by the 40m SSB and CW stations. The low antennas caused their signals to travel nearly straight up into the Ionosphere (close to a 90 degree take-off angle with respect to the ground producing nearly vertical incidents with the Ionosphere). Within the Ionosphere the signals were reflected and refracted back towards the Earth, and travel nearly straight down to a location not very far from the transmitter. The signals were then reflected by the Earth again nearly straight up into the Ionosphere, and so on. As a result, the hop distance for the two 40m stations was very short. The 40m signals literally bounced their way across the west, picking up every western ARRL Section in the process, until the signals died out east of Colorado. The performance of the two 40m stations illustrates the value of using NVIS propagation on 80 and 40 meters for emergency regional communications, that is, for emergencies in which it is vital that communications be maintained with all stations in a given geographical region. The critical frequency of the Ionosphere prevents NVIS from being used at frequencies above 40 meters (20m, 15m, etc.) At times, the critical frequency is below the 40 meter band, meaning that 80 meters is the only band capable of supporting regional NVIS communications.
Our Field Day Chairman, Tom Stough W0UFC, expresses his thanks to everyone who participated in Field Day 2003. Special thanks to all the band captains, to Jonathan Becker for arranging the barbecue, Jeff Reinhardt for publicity, and Paula Larson and Alberta Munding for providing dessert and errand-running. A special thanks to Mr. John Byrd for letting us use his hill top again this year. Greg Lane K7SDW would also like to personally thank all the hams that came out to our site and especially those who mentored others needing help and direction to make Field Day fun and enjoyable for everyone.
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