Re: Group Posts - The Numbers

Gary DeBock

On Sun, Oct 2, 2022 at 12:20 PM, Robert Conboy wrote:
What I find most useful, is when I get an idea from what someone else has done, or when someone asks a question/has a problem that I know a good answer to / solution for.
The biggest revelation I learned came soon after joining this group: 
Others had discovered and experimented with “ferrite sleeves” around the same time I was, roughly 18 years ago. It never occurred to me that the concept was innovative, nor did I know anyone who would have appreciated it at the time.
I particularly like the direction Gary took his basic design: evolving it toward portable practicality and lower cost. Doing so made it more accessible to others and has advanced the state of the hobby. 
My designs were done in isolation from any dx community and evolved in a different direction. High cost and high complexity, with housings, vernier dials, low noise amps, contoured feedback networks for regeneration,  and powered by lithium batteries.
Hi Robert,

Thanks for your comments.

It's always very interesting to have different hobbyists go in different design directions when tweaking an antenna for maximum performance. The FSL antenna has been a classic example with all kinds of shapes, sizes and components used over the past 12 years.

After Graham Maynard published his "ferrite sleeve" article: in 2011 (along with some rather dubious scientific claims) there were three of us in the Ultralight group which took the concept and ran with it, finally constructing huge "gain monsters" of limited practicality. My own contribution to this wacky challenge was a building a 17 inch (43cm) diameter monster FSL which cost $1K+, weighed in at 38 lbs. (17 kg) and featured 129 Russian surplus 200mm x 100mm ferrite rods. The antenna provided plenty of DXing gain, but essentially was a vanity project, since almost nobody else could afford to build one.

Shrinking the FSL down to a practical size really made the antenna more popular, accessible and more fun to use-- and now, even I routinely use the 6" and 8" models during ocean beach runs instead of the 15" and 17" monsters. When the DX propagation is there a 6" or 8" FSL will do the job-- and when the propagation isn't there, you are wasting your time even with a 17" monster.

73, Gary

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