Commonly published information tells us winding a choke or 1:1 balun on a toroid with this special winding technique increases common mode impedance (choking isolation) of an 11-turn balun on a pair of #65 material ferrite cores: The common mode rejection sweep, assuming a 50-ohm common mode source and load is: (pardon the camera jitter) […]
Continue ReadingAuthor: John A. Brackemyre, K7EFX, Stockton, California © June 1, 2010 Design ScopeThe purpose of this build was to replace my 12/6-Meter inverted-vee with a rotatable antenna. Being a Special Effects designer and machinist I had all of the parts so I designed around what was in my collection of tubing, clamps and hardware. Using […]
Continue ReadingDipole Antennas – the Effect of Height Above Ground I frequently hear the question: how high should my dipole be? Or alternatively, will my dipole work well at this or that height? Unfortunately, these questions can not be answered without first stating what you want the dipole to actually DO, i.e. how you plan to […]
Continue ReadingThe Umbrella This post describes a simple, easy to make and erect portable vertical antenna for the low bands (160, 80 and 40M). {ed. 80, 40, 20 and 15M were proven at FD 2018} This one is 30 feet high with a unique top hat, utilizing an SG-230 Smartuner and a single elevated radial. It has […]
Continue ReadingThanks to Simone Mannini IW5EDI -May 28, 20202039 – DX Zone With the new WSJT-X version 2.2.0-rc2, now available for downloading from the WSJT-X website the WSJT-X development team has also published additional FT8 “overflow” frequencies: Increasing FT8 usage on the popular bands 40, 30, and 20m means that the default 3 kHz sub-bands are often wall-to-wall with signals. Overcrowding encourages some […]
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The ham radio HF antenna, of the half-wave dipole variety, requires a lot of horizontal space. This Page Covers1. “Full Sloper” Dipole 2. Inverted “V” Dipole 3. Inverted “U” Dipole It’s possible, however, to “fit” a full-length half-wave dipole in less horizontal space, while retaining most, if not all the advantages of the “classic dipole” described elsewhere on this site. (See Antenna Section […]
Continue ReadingPosted by Sean Kutzko, KX9X on February 21, 2020 at 7:22 pm Most Hams dream of giant towers with large rotatable antenna arrays perched on top. However, many Hams can’t put up such workhorses. Some common issues we run up against are budgets, restrictions on outdoor antennas due to covenants, simple lack of real estate, or the […]
Continue ReadingBy Don Keith N4KC Copyright 2018 by Don Keith Some of us give up too easily. Or we are too timid to give something new a try. I have seen several examples of this lately. One was a new amateur who got all excited after he upgraded, acquired a perfectly adequate HF station, but then […]
Continue ReadingFor Immediate ReleasePress Release #11Feb. 2, 2020 We’re on autopilot, next stop Punta Arenas, Chile. The project is on scheduleTeam members will begin arriving in Punta Arenas on February 9th, Braveheart is scheduled to arrive on February 13th, we load the ship on Feb 14th and depart on Feb 15th for Signy Island. Nigel Jolly will have already […]
Continue ReadingARRL report a powerful magnitude 6.8 earthquake struck the province of Elazig on January 24, radio amateurs assisted in the response Aziz Sasa, TA1E, at TRAC Headquarters reported, “The affected area was very small and the intensity limited; our involvement was also limited.” He said two TRAC branches in the affected area stepped in, assisting […]
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