Posted: 8/13/2015 9:29:48 PM EDT
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I've been wanting to try a magloop antenna for awhile. My portable vertical works well but laying out the counterpoises is a bit of a pain. Today I was down in New Castle, DE for work, just down the road from HRO, and an AlexLoop Walkham 40M to 10M magloop came home with me. I set it up out back after work, along with my Mac, KF5INZ digital interface, and Yaesu FT-817ND.   That knob on the bottom of the box is used to tune the antenna. Although you're supposed to have an SWR meter inline so you can tune it when transmitting, dummy me forgot to get a BNC-to-UHF adapter, so I had to make do with the FT-817ND's built-in SWR meter. I played around with the setup for a couple hours, mostly on 20M PSK31. I heard stations from as far West as CO, down into GA, and as far East as the Balkans including Serbia and Bulgaria, along with Poland, Slovakia, Spain, and Italy. I completed two QSOs. One was with a ham in MO and the other with Italy. Workmanship of the AlexLoop is very good, it's light, and setup/takedown are easy and fast. As a small magloop, bandwidth is very narrow so if you change frequency even a few kHz you need to retune. When oriented vertically the radiation pattern is almost omnidirectional but there are two strong, narrow nulls perpendicular to the loop. They could be useful to minimize QRM. I'm also interested in seeing if it'll work for 40M NVIS. |
| Cool! Those nulls you mention are great for direction finding noise sources. You use the null to pinpoint them, and the null is so sharp that you can triangulate in on a signal really easy. I found many power line noise sources that way with one I built for 40 Meters, but it was for receive only. |