Topband: Topband Antennas/FCP

[Charlie Young]

It is great to see the technical discussion regarding topband antennas, particularly the FCP.  Thanks to K2AV for putting his ideas and design out there for peer review.  Hopefully the review process won't discourage folks like myself, who are not antenna enginers, from trying various ideas, including the FCP in limited space.   
 
I agree antennas do not work due to magic.  As N6BT said, everything works.  Some things work better than others.  Measurng how much better one thing works than another, on an engineering basis, is the difficult part.  Most of us have to resort to the Gotham method.  Who can we work?  How difficult is it to work stations with the current antenna compared to previous antennas?  How do our contest scores compare with previous efforts?   Without A/B testing, these evaluations are subjective but over time, an experienced op gets a feel for a relative level of performance. 
 
Those of us who have learned antenna modeling  have a way to do technical comparisons of antennas up to a point but there are limitations. For example, I have never been able to duplicate real world effects in the models of my tree supported inverted L elevated radials.  My models don't show the significant effect of close proximity to ground on the radial resonant length.  Consequently, I just build the antennas, adjust the radials to the real world length, and don't worry about what the model says.   In my case, it is simply not feasible to have an elaborate ground system, for various reasons.  
 
My point  is to encourage folks to study theory and try to understand the technical aspects of antennas but, absent ideal installation conditions,  to put something in the air and try it.  If you have limited radial space, try the K2AV FCP.  It is not complex or difficult to build.  I don't know if it will work as well as two resonant elevated radials and doubt if the model will tell me, due to close proximity to the earth.  However, I do believe the FCP does achieve a level of perfomance better than what users have achieved with prior limited space antennas.  Again, these are experienced ops, not a bunch of novices who get a leg tingle over working EU.  
 
I intend to try a FCP and do A vs B testing on my site.  Likely this will wait until the rattlers and copperheads slow down in the fall.  My goal is to see if equivalent performance can be achieved between the FCP and a few elevated radials, to save the real estate for rx antennas.  
 
Antenna experts would laugh at my simple antennas and minimal radial systems.  However, they have been good for 216 countries and 37 zones since October 2008 on 160.  Several of my WVDXA friends have confirmed 160 DXCC with a single elevated radial. One just has to try stuff, and do the best one can with the available resources.         
 
Build something and get on 160!   In 50 years of operating, I have had more fun on 160 than any other activity, period. 
 
73 Charlie N8RR