As requested. Parts:
http://thewireman.com/wirep.html#631 #635 Double polyimide insulated #14 AWG, 15 feet. https://www.amidoncorp.com/categories/15 #12 AWG standard wall teflon tubing, 15 feet. https://www.amidoncorp.com/items/26 T300A-2 #2 material powdered iron toroid. You can also use Micrometals T300-2D, or a PAIR of Micrometals T300-2 stacked and taped together with fiberglass tape, which are the same as Amidon T300A-2. You can often find the Micrometals cores on eBay. Note: The core material, bifilar winding turn count, and core dimensions are chosen to facilitate a "simple" 160 installation that has approximately 1/4 wave wire, a toroid wound balun-sized isolation transformer feeding the coax, and a folded counterpoise attached, that delivers an impedance that is close enough to 50 ohms resistive to reasonably use regular coax as a feed. If you change the turn count, or the core material, or core dimensions, this balance for the "simple solution" is defeated, and the conditions which were tested in our two year research period no longer apply. You might substitute configurations which we put up ourselves, tested, and specifically rejected for cause. Like burned it up, was lossy, wouldn't stay tuned, was worse than the original antenna, etc, etc You can't use a stack of smaller diameter cores with the same total of A sub L numbers because you can't get the required 20 bifilar turns on the inside diameter of the smaller cores. 20 turns fills up the inside diameter of the T300x-x form factor. If you don't use 20 turns, then you will get less inductive reactance to cancel the FCP's capacitive reactance for the simple installation and need more wire in the radiator to compensate. Dropping only one turn on the core will add 12 or 13 feet to the "pruned" length for resonance you would have had otherwise. The #2 powdered iron core material has been very carefully chosen for 1.8 MHz QRP and QRO, drawing on advice and published work by W2FMI. Do not substitute ferrite or other powdered iron materials. #2 powdered iron cores are always painted red and easily identified. A core without paint or a different color will not work. Winding: First, have a look on W0UCE's site for a good picture of one of these correctly done . (Pix worth 1000 words and all that...) http://www.w0uce.net/K2AVantennas.html Scroll down for the pictures. Note the appearance of the bifilar pair when done right. Think of the bifilar pair as an exotic "zip cord". You will be winding the PAIR as if you were winding with zip cord. The professionally wound version from Balun Designs with enclosure and hardware can be seen at: http://www.balundesigns.com/servlet/the-108/1-cln-1-High-Isolation-Balun/Detail Cut wire and tubing in half and slip the wire inside the tubing to create a pair of parallel 7.5 feet teflon-sleeved wires. Some find it easier to handle the wires in winding if you tape them together. Tightly wind twenty bifilar turns around the core. This will use all the space in the inner diameter. Keep the bifilar pair turns separate and uniformly spaced on the outside. ALL the wires should be laying flat on the toroid, with NO twist flips where the wires do an "over-under". IMPORTANT: When properly connected there is NO connection between the antenna/FCP side and the coax side. CAUTION: If you get that WRONG when you hook it up, you will STILL be able to hear on it, but the system won't work right and you will loose valuable dB's. !!! VERIFY THE SEPARATION !!! with an ohmmeter BEFORE you start pruning the antenna wire or hurling electronic curses at dog, family, neighbors, or me. To wind one of these for a 16+16 version FCP for 80 meters, and you are doing the "simple" version with 67 feet or so radiator above the FCP, evenly space *fifteen* bifilar turns around the toroid. 73, and I'm looking forward to a lot more 160 QSO's in the contests, Guy K2AV On Sat, Dec 10, 2011 at 1:38 PM, Bob Garrett <rgarre...@comcast.net> wrote: > Hello Guy, > > When the dust settles, will you post a list of parts and sources so we can > duplicate this antenna and the unique matching network? 73, Bob K3UL > _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK