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From: Maurice Hately GM3HAT
Date: 10 Mar 2003
Time: 16:15:47
Remote Name: 80.225.138.81
Referring to Crossed Field Loops, Steve Nichols G0KYA writing a Review Article in the RSGB Magazine RAD COM in May 2002 pages 28-30 states "No interaction on receive or on transmit was noticeable as the magnetic loops [he had also in use} were swung past the same resonant points as the CFL's" The CFL design generates principally radiation field and nearly all the energy flows away. A CFL has a negligibly small NEAR FIELD and consequently achieves almost total isolation. All user of the classical high Q, high voltage, Magnetic Loops know that these antennas have a worrisome tendency to go out of tune when their environment changes e.g. a person approaches the antenna, or a tree-branch sways near to it in a gale. This does not happen with a CFL as Steve Nichols confirms. Why David and Alan do not make a CFL or ( Dual Cionductor Antenna) to try this I cannot understand. The design is given in full in the UK Patent GB2,330.695 and US 6,025,813. Or there is a complete summary of the development of the CFL from 1980 to 2000 given in the Mercury Magazine July 2001,(Journal of the Royal Signals Amateur Radio Society. Alan G3NOQ refers to a paper by Martin Smith in ELectronics Letters Feb 1992. A very early case of an investigator who failed to get two resonant circuits out of phase by plus and minus 45 degrees and so missed finding the actual CFA effect. Many others since then have also done it. When I wrote a rebuttal article to the same journal pointing out the probable error, the Editor refused to publish it. Happily the Antennex Magazine editor is more fair-minded and encourages full debate until the issues are clear. Thank you,Sir. Maurice Hately, GM3HAT