<<< Have you ever measured Q of any of your FSLs?
I thought Q was important from when I first heard of the FSL,
although, when a guru responded in an email,
"Q has next to no relation to how the FSL will actually perform."I questioned him on that, he got mad, and stopped responding to my email.
In answer to your question, I don't measure Q on my FSL antennas because I have found that direct A/B weak signal testing is the most effective way to optimize components in FSL antenna designs. For example, since 1162/46 Litz wire significantly outperforms 660/46 Litz wire, and the "384P" variable caps significantly outperform "365P" variable caps, it's a pretty simple matter to determine which of these components to incorporate into a new FSL antenna design.
Despite this, I disagree with the guru who said that "Q has no relation to how the FSL will actually perform." Most of the initial FSL construction ideas were borrowed from the Crystal Radio Group enthusiasts, especially Steve R., who was one of the three original FSL antenna developers. Q measurements are extremely important in the crystal radio group, optimizing antenna components, dielectric materials, coil shapes, etc. A lot of this experimentation is applicable to FSL antenna designs, but we also face the additional challenge of designing rugged, weather-resistant antennas that can survive in rough environments like ocean cliffs, as well as survive rough handling during transoceanic air travel. As such, rugged components, frames and Litz wire are chosen strictly based on their ability to provide the maximum inductive coupling gain in the smallest possible size and weight. Viewers of the new 3 inch Baby FSL demo video can see the end result of this process :-)
73, Gary DeBock (in Puyallup, WA, USA)