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Re: [IRCA] FSL Antennas-- Truth and Fiction

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 Thanks for the great FSLs and the great article. I attended a superb Grayland TP DX session in 2006 after the Seaside, OR IRCA Convention hosted by Pat Martin. I packed copious lengths of wire which were used for BOGs. I anticipated returning to the PNW for subsequent TP DXing sessions for some time before it happened. I attempted to set up what I thought was a temporary corner-fed loop friendly VRBO. After I reserved the oceanfront cabin, on a nice cliff overlooking the Pacific, it turned out the neighbors were intolerant of anything obstructing their views. Then the Grayland motel closed, shortly before I planned my return.
I appreciate the efforts of Guy Atkins and Bill Whitaker identifying three wire antenna-friendly locations on the Pacific coast. Guy also provided me with excellent information on a portable tent pole loop which I plan on putting together and testing.

While I was in Lincoln City, I tried an indoor corner-fed loop with an FLG-100. The QRM from the room rendered the attempt futile. The issue I am faced with is the power source for the FLG-100. I don't fancy the thought of explaining Gel Cells to TSA. I fear I would wind up on the 6 O'Clock news should I attempt air travel with those. Driving out to the Pacific Coast is a long two day trip, each way.
I can attest to the effectiveness and portability of the TSA-Friendly FSLs. My first taste of FSL-enhanced travelling DXing was at Kalaloch, WA then at Rockaway Beach, OR. The FSL I used at the time was a smaller 3.5" unit which made the difference of decent DX vs. extremely limited DX. The FSL was used in conjunction with a stock Tecsun PL-310. Gary then generously provided a 5" Bar TSA-Friendly FSL which I took to Kalaloch, then to Kauai and the Big Island, Hawaii. TP DX at Kalaloch was decent. TP DX at Princeville, Kauai was a jaw-dropping experience for me. Using an azimuthal map centered on Princeville , I suspected that Princeville might be a decent northern Asian TP Dxing location. Asian DX there wildly surpassed my expectations. Having read the DU TP DX reports from other TP DXers I figured the west side of the Big Island might also be decent for DU TP DX.Â

Gary's TSA-Friendly FSLs fill a major need in that they are transportable via air and require no additional power source. Gary went above and beyond again providing me with a Supercharged Tecsun PL-380 which, when used in conjunction with a TSA-Friendly FSL makes for an extremely potent DXiing combo. On both of my Hawaii trips, the FSLs were easily positioned on an outdoor picnic table near the water's edge. I use Google maps to try to identify vacation rentals equipped with strategically placed outdoor picnic tables as I do not travel with the excellent FSL stands Gary constructed for Rockworks DXpeditions. Speaking of Rockworks, I brought my 5" Bar FSL to Rockworks this past August. Depsite my efforts to carefully pack the unit, it began to demonstrate some effects from the mileage it had traversed resulting in degraded low band performance. Gary came to the rescue with a spare 5" Rod TSA-Friendly FSL which worked very nicely at Rockworks. I highly enjoyed hearing More FM on 531, as well as Chinese Radio on 936, among many other DUs..
Using the Supercharged Tecsun PL-380 in conjunction with the 5" TSA-Friendly FSL has resulted in getting much more from long distance DXpeditioning. At Rockworks Chuck Hutton asked me if I got my money's worth from the trip. Thanks to the Supercharged Tecsun PL-380 and the 5" Rod TSA-Friendly FSL my answer was a resounding YES!! I have already reserved my room near Rockworks for the first week in August next year.
Many Thanks Gary for Your Hobby Enhancing Efforts!
Craig BarnesWheat Ridge, CO


    On Thursday, October 4, 2018, 3:16:14 AM MDT, Gary DeBock <d1028gary@xxxxxxxxxxx> wrote:  
 
 The development of modern Ferrite Sleeve Loop antennas has been one of the most remarkable antenna breakthroughs of the 21st century, but since none of these have ever been mass produced for commercial sale, a lot of questions and misconceptions about their function and effectiveness persist in the general AM-DXing community. This brief message is an attempt to clear up some of the more common misconceptions.


Modern FSL antennas are based upon an experimental article published by the U.K.'s Graham Maynard in February of 2011, describing a cylindrical collection of ferrite rods wrapped by a wire coil, and tuned by a variable capacitor to resonate with (and provide an inductively coupled gain boost for) a nearby portable radio tuned to the same frequency http://www.zen22142.zen.co.uk/Media/fsi.htm

Graham's original article included quite a bit of "unusual" scientific theory (for which he was roundly criticized) and provoked accusations of design plagiarism and exaggerated performance claims. Flying "under the radar," however, three dedicated antenna experimenters in the relatively new Ultralight Radio enthusiast group (Steve Ratzlaff, Kevin Schanilec and yours truly) began extensive, all-out experimentation in the new FSL design to test it out in the "real world" of ocean coast transoceanic DXing-- both on Longwave and Medium Wave.


Steve, Kevin and I shared information on which components were the most effective, and which designs seemed to provide the highest gain. For a brief time we all worked toward the goal of maximum gain, purchasing huge lots of 200mm x 10mm ferrite rods from the Ukraine (to the delight of the eBay sellers, who must now be enjoying early retirement). Of course we didn't all agree on the design factors influencing maximum gain, but one thing was becoming very obvious-- this new antenna had a compact gain advantage like none other in radio history.


Given the fact that this new antenna could provide tons of gain from an extremely small "footprint," I knew that this innovative antenna finally provided an ideal chance to test out a fascinating new theory that I've always believed in-- that an ocean cliff's flat shape could enhance transoceanic DX reception far beyond that possible on a nearby flat ocean beach. In early 2011 this idea was laughed off by almost all of the transoceanic DXers, who had routinely set up their huge broadband antennas on flat ocean beaches for decades. Nobody had ever tried a serious DXpedition on a plunging ocean side cliff, since there wasn't enough space at such sites to set up a "serious" broadband antenna-- or so they thought. But they were about to be proven wrong.


An early 8" (20cm) diameter FSL antenna was set up at two plunging Oregon coast cliffs in the summer of 2012-- at Rockwork 4 (near Manzanita), and at Cape Perpetua (near Yachats). Immediately the new FSL antenna began receiving multiple New Zealand stations that had never been heard on the North American west coast, including 531-More FM, 585-Radio Ngati Porou, 765-Radio Kahungunu and 828-Trackside. Perseus-SDR DXer Chuck Hutton was interested enough to join me for a July 2014 Rockwork 4 DXpedition, during which the all-time Grayland record for New Zealand reception was completely shattered-- 88 Kiwi stations (compared to 61 at Grayland). Chuck's broadband antenna was a tiny version of the Grayland monsters, but ocean cliff propagation enhancement more than made up the difference.


A side effect of the ocean cliff "Monster FSL" development was, unfortunately, the "expensive and heavy" reputation that currently ligers in the AM-DXing community. It was commonly joked that these new antennas could "shut down an airport without really trying," that a body builder would need to deploy them, and that they were far beyond the means of the average DXer. In late 2016 a new type of compact, lightweight FSL was designed to dispel all of these misconceptions, however-- the "Frequent Flyer" FSL antennas.


Even though the new antennas had proven to be the ultimate compact gain performers, it was a radical design concept to shrink the antenna down to a miniature size for TSA acceptance, while retaining enough gain performance to be a real thriller on exotic ocean beaches. The construction cost would need to be acceptable for the majority of DXers, and the design would need to survive a lot of travel abuse. In late 2016 two new "Frequent Flyer" FSL designs were finally built, and throughout 2017 Craig Barnes and I tested them out in thrilling Hawaii DXpeditions, tracking down all sorts of exotic Pacific island DX. Pete Taylor took one of the models on European and Caribbean cruises, and in April I had the hobby thrill of a lifetime in the Cook Islands, tracking down long range AM-DX stations in India (at over 8,000 miles), Bangladesh, Mongolia, Cambodia and Brazil-- all with a radio and antenna that easily fit within hand carry luggage.


In an effort to make these compact, TSA-friendly FSL antennas available to more DXers there were 10 models given out last year, and a full "Heathkit-like" construction article for the 3.5 inch "Baby FSL" model was written, and posted at http://www.mediafire.com/file/pnfm8909c77zjoy/3.5inch-FF-FSL.doc/file

More resources and refinements will be devoted to these "Frequent Flyer" FSL antennas this year, with the goal of making these breakthrough models accessible to all interested DXers. Whether your preference is to chase long range DX on an exotic ocean beach or simply have thrilling portable DXing sessions close to home, this new type of antenna may be your ticket to increased hobby excitement.


73 and Good DX,

Gary DeBock (in Puyallup, WA, USA)Â Â Â Â 
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