Claudio Capelli, I4LEC, had a long, 30-year history in competitive HF contesting that ended with his successful 2010 WPX SSB effort from NQ4I in Georgia. After that contest, Claudio abruptly shifted his interests toward other facets of the hobby; primarily, tailored antenna setups based on specific locations and orography, challenging the conventional belief that more elements, longer booms, and higher antennas are always better. He advocated for a "do more with less" approach, ensuring each setup was optimized for its environment. His knowledge and experience with antenna design and selection, buttressed by HFTA and extensive experimentation, are impressive. Claudio has also turned his attention to SDR platforms, rig performance and measurements, and innovative antenna designs. The discussion provides unique insights and perspectives, inspiring us all to delve further into the technical aspects of ham radio that contribute to improved performance. Please join us for the conversation, and if you like what you hear, please subscribe to W1DED Worldwide Ham Radio. 73, Kevin W1DED
I have no idea what 'more with less' is supposed to mean. Antennas are current carriers that are radiating resonators. The power patterm attributes are enabled by constructive and destructive interference. Near field is exploited for impedance, bandwidth, and power pattern. The box that hams still get stuck in is the assumption that Yagis 'have to be a certain way'. That has long since been shown false, as per the pioneering work of Jim Breakall WA3FET with the OWA. If there is a link on Claudio's innovative antenna design, I am sure many of us would enjoy reviewing it , in the context of what has already been done and what is already known. It is unfortunate and certainly to the praise of I4LEC , that hams have taken so long to accept that terrain is a factor in antenna choices. My second home in NH has a mountain ridge that funnels NE. You can bet that I am planning antennas that take advantage of that funneling because I know that the right set of antenna will enjoy up to a 10 dB 'waveguide' increase from the terrain. BTW,.'designing for environment' is how antennas ARE designed and is not unique to any individual.That philosophy has been implemented for decades. 73 Chip W1YW
There is also the idea you need a Yagi on a tower to easily work HF DX. My back yard is basically a large clay pot that collects water. The neighbors to the North are on higher ground. Water from their yard flows into mine after it rains. If it rains, it may be better to mow after the rain has dried off than to wait the until the next day when the water has made its way into my yard! Over the last twenty years I've added lots of rich organic matter and fertilizer to grow roses so the soil conductivity is extremely high. My 80M wire vertical works extremely well for working long distance DX! I'm experimenting with a height of just 30 ft and continue to work lots of Australian stations over the summer on 80! Also works on SSB voice. Just a half dozen more for DXCC on 75 Phone. One may want to consider the possibility of modest wires in the trees and wire verticals when hunting for a new location that is close to good schools and shopping. I know someone whose backyard woods got transformed into a Solar Farm!
Hackers use social engineering to break into computer systems. Social engineering is just as important with antennas! I know a ham in the suburbs who put up several antennas without issue. Then he put up a vertical in front of the window a neighbor looks out of every morning! Big mistake! The neighbor complained and now he has to get a permit for that antenna! He says that cost him big $$$. That is also bad from an RF engineering point of view. Antennas should be placed as far away from occupied buildings as possible to minimize RF exposure and Radio Frequency Interference. Automatic antenna tuners mounted at the feed point allow the use of long feedlines as the SWR on the feedline is low. Lowering the received noise levels by a couple of S-units can be a huge win toward optimum antenna performance if it only costs a fraction of a dB in transmit efficiency.
HFTA is another program that isn't supported by the author, as Dean Straw retired a long time ago. It is companion software to the ARRL Antenna book. It was so long ago that the Ward Silver was Antenna Book editor for years and then retired. Ward was not a software person and did not update HFTA. Microdem is no longer useful to hams. The best source of terrain data is the servers at k6tu.com, as hams have not been able to use the government servers for years. They change the data format.
Thank you for an interesting interview! Less can be more. Do an EZNEC of a 20m dipole height at 1/2 wavelength. See the "theoretical gain" that occurs by raising the dipole. If I remember from doing it myself, you'd have to raise the dipole upt to 1 1/2 waves above ground (or thereabouts) to achieve the same theoretical gain. Remember, propagation is the ultimate "casino". Antenna horizon (terrain affected, structure affected, even plant life affected) are key also. Never concerned myself with takeoff angle; just knowing that band, time of day made the difference for 100W phone DX.
EZNEC cannot model terrain. The takeoff angle is affected by the terrain, at least from gradients from flat. Most DX is done through multihop. That is best enabled by low takeoff angles. So, yes, you do have to 'worry' about it. 73 Chip W1YW
Not me Chip. I realize multi-hop and I understand theory, but in practice, I just liked to operate when I had an HF setup. So for me, didn't and won't matter until I die. I'm in this to have fun, and, where I can "Chip in" (like how I used your name ha!) into emergency service and orientation to the hobby for non-hams. Thanks though for your comment. Have great day!
Still, even the testing pool has question on this....IOW it is part of the knowledge base we acquire through licensing. If multihop conditions are good, then even if your launch angle is high (say, greater than 40 degrees) your ERP may be tens of watts or more at the lower elevation angles, while peaking at 100-400 watts (at peak gain) . In 'good conditions', this certainly allows marginal or modest DX contacts. The SFI is now higher than it has been in decades, so expect great prop this Fall! 73 Chip W1YW
HFTA will model Yagis over flat terrain and provide propagation statistics to help choose the best height for a particular path and band. VOACAP will model that for a particular solar flux and month of the year. HFTA provides an average over the entire solar cycle. The HFTA figure of merit can be useful for those who don't have time to study propagation.
