I was packing things for a move and came across an old QST magazine* where I found something that may be of interest in this regard; the "pennant," "tag" or "diamond" terminated receiving antenna. Designed for frequencies of 1.8 MHz to 7 Mhz, they're some 14 feet high and 28 feet from end to end. If scaled, we'd have a "probe" perhaps 6 inches high and one foot long. I suspect a diamond would offer wider frequency coverage than a flag due to a more gradual transition from feed point and termination.
Caveats: 1) The impedance and termination are 925 ohms (diamond), the pennant and flag versions being a little different. They require broad-band matching, such as Tom Rauch's (W8JI) design mentioned, using a binocular ferrite core with 8.5 turns >from the antenna and 2 turns from the feedline. This will affect the frequency coverage possible. 2) The writer says these run -30 to -36 "gain" dBi. This mandates a preamplifier at the antenna. We all HAVE one, right? *Flags, Pennant and Other Ground- Independent Low-Band Receiving Antennas; Earl W. Cunningham, K6SE. QST Magazine, July 2000. Page 34 Cortland Richmond This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
