Digital Modes Meanderings
Antenna Performance or “How well does it work?”
The obvious question that comes to mind when one reads about an antenna system design is, “How well does it work?”. That is a fair question, but not one that is always easily answered. It really depends on the original design parameters and how many of those parameters were achieved. In the case of the antenna system that I was attempting to create the original design parameters included high radiation efficiency, low system loss, easy matching capability, DX (long distance) communications capability, multi-band operation capability, high power capability and low physical profile (for stealthy HOA operations). Those were some serious design parameters to expect from one antenna system. I was not sure in the beginning that it was possible to achieve all of these “wish list” items. But if you are going to wish, you should wish big. In the end, all of these parameters were successfully achieved. It only took 10 years! The end result was my open wire line fed vertical doublet.
The one parameter that was not specified in the original design specifications was antenna gain. It was expected from the beginning that the gain from whatever antenna design that was finally chosen was going to be rather low. However, the system’s low loss, high radiation efficiency and low angle of radiation helped to offset any negative impact from the anticipated low gain. It should also be remembered that this antenna system was designed for an antenna restricted area. So having any antenna outdoors operating at any level of performance is an achievement. So with that as a consideration, the overall level of performance that was achieved is (in my opinion) extremely good. One measure of the results for the vertical doublet antenna system is documented below. These results are not one-time-only contacts. Some have been duplicated several times. It works for me. As always, your mileage (literally) may vary (YMMV).
The one parameter that was not specified in the original design specifications was antenna gain. It was expected from the beginning that the gain from whatever antenna design that was finally chosen was going to be rather low. However, the system’s low loss, high radiation efficiency and low angle of radiation helped to offset any negative impact from the anticipated low gain. It should also be remembered that this antenna system was designed for an antenna restricted area. So having any antenna outdoors operating at any level of performance is an achievement. So with that as a consideration, the overall level of performance that was achieved is (in my opinion) extremely good. One measure of the results for the vertical doublet antenna system is documented below. These results are not one-time-only contacts. Some have been duplicated several times. It works for me. As always, your mileage (literally) may vary (YMMV).
Top Two Farthest DX Contacts on each Band as of February 2015
South Africa, ZS6WN, 9069.5 mi (14595.9 km), 40 meter band, FELD HELL
Philippines, DV1JM, 8559.5 mi (13775.1 km), 40 meter band, PSK31
---------------------------------------------------------------------------------------------------------
Australia, VK3AMA, 8951.1 mi (14405.5 km), 30 meter band, PSK31
Philippines, DV1JM, 8559.5 mi (13775.1 km), 30 meter band, PSK31
---------------------------------------------------------------------------------------------------------
Reunion Island, FR4PG, 10565.7 mi (17003.9 km), 20 meter band, PSK31
Australia, VK6GWM, 10539.5 mi (16690.9 km), 20 meter band, PSK31
---------------------------------------------------------------------------------------------------------
Australia, VK6BBT, 10548.5 (16975.4 km), 17 meter band, OLIVIA
Japan, JA7WND, 6373.2 mi (10256.7 km), 17 meter band, PSK31
---------------------------------------------------------------------------------------------------------
## Mauritius, 3B8IK, 10641.2 mi (17125.8 km), 15 meter band, OLIVIA
Australia, VK4LDX, 8475.7 mi (13640.4 km), 15 meter band, PSK31
---------------------------------------------------------------------------------------------------------
Japan, JO1WKO, 6652.4 mi (10705.9 km), 12 meter band, PSK31
South Cook Islands, E51BQ, 5524.5 mi (8890.8 km), 12 meter band, OLIVIA
---------------------------------------------------------------------------------------------------------
Australia, VK7KT, 8968.8 mi (14433.3 km), 10 meter band, PSK31
South Korea, DS4GQR, 7164.1 mi (11529.5 km), 10 meter band, PSK31
## - Top Mileage
NOTE: All but two (2) of these contacts were made with 60 watts PEP or less.
South Africa, ZS6WN, 9069.5 mi (14595.9 km), 40 meter band, FELD HELL
Philippines, DV1JM, 8559.5 mi (13775.1 km), 40 meter band, PSK31
---------------------------------------------------------------------------------------------------------
Australia, VK3AMA, 8951.1 mi (14405.5 km), 30 meter band, PSK31
Philippines, DV1JM, 8559.5 mi (13775.1 km), 30 meter band, PSK31
---------------------------------------------------------------------------------------------------------
Reunion Island, FR4PG, 10565.7 mi (17003.9 km), 20 meter band, PSK31
Australia, VK6GWM, 10539.5 mi (16690.9 km), 20 meter band, PSK31
---------------------------------------------------------------------------------------------------------
Australia, VK6BBT, 10548.5 (16975.4 km), 17 meter band, OLIVIA
Japan, JA7WND, 6373.2 mi (10256.7 km), 17 meter band, PSK31
---------------------------------------------------------------------------------------------------------
## Mauritius, 3B8IK, 10641.2 mi (17125.8 km), 15 meter band, OLIVIA
Australia, VK4LDX, 8475.7 mi (13640.4 km), 15 meter band, PSK31
---------------------------------------------------------------------------------------------------------
Japan, JO1WKO, 6652.4 mi (10705.9 km), 12 meter band, PSK31
South Cook Islands, E51BQ, 5524.5 mi (8890.8 km), 12 meter band, OLIVIA
---------------------------------------------------------------------------------------------------------
Australia, VK7KT, 8968.8 mi (14433.3 km), 10 meter band, PSK31
South Korea, DS4GQR, 7164.1 mi (11529.5 km), 10 meter band, PSK31
## - Top Mileage
NOTE: All but two (2) of these contacts were made with 60 watts PEP or less.