Topband: Pixel Technologies Magnetic RX Loop
w2pm at aol.com
Mon May 9 04:12:52 PDT 2011
I notice they repeat the incorrect assertion that these magnetic loops work by being sensitive to the "magnetic field" rather than the electric field and that has been long shown to be false - these antennas are not sensitive to the magnetic field at all but very close proximity to the sources. And while their literature does refer to the "figure 8" pattern - they don't stress the fact the pattern IS the advantage of this antenna as the extreme null inside the Fig 8 loop pattern is what you aim to the noise source to null it out. If you have multiple noise sources you get to choose only one. None the less if you are really very local challenged this antenna can be quite helpful but a small flag or pennant is clearly superior. In fact the late great K6SE's mini diamond loop is the same size and offers all the usual advantages of cardiodal patterns and fairly low take off angle. These mag loops have a 360 degree vertical "pattern" AND they are single banded, often very narrow in bandwidth too within the same band.
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On May 7, 2011, at 19:25, wb6rse1 at mac.com wrote:
> The Pixel Technologies PRO-1A Magnetic Receiving Loop was demonstrated at the Visalia DX Convention last month. It's about the same size as a circular or diamond shaped coax loop. It includes a preamp mounted at the feed point. The antenna has had several positive reviews on eHam.
> Joe, W4TV, posted to the list earlier this year looking for references for the Pixel design. The technology is based on work done by Dr. Carl E. Baum in the mid '60s through the early '70s. A list of papers complied by Dr. Baum appears here:
> Of particular interest regarding the Mobius design are: SSN notes 7, 25 and 127 including a discussion of multi-turn Mobius loops.
> A coax loop has its shield split opposite the feed point but the center conductor is unbroken. Based upon the references above, the break opposite the feed point in the Mobius design is in both the shield and the center conductor with the shield of each side connected to the center conductor of the opposite side.
> If you've built your own Mobius receiving loop of tried the commercial product, a report of your experience would be of great interest to the Top Band list.
> 73 - Steve WB6RSE
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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