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                                K9AY RX Loop

Things are starting to feel better on the high bands as I build and install the stacked Yagi's, but I was still having trouble hearing through all the noise on the low bands. 

After W5WZ's success with long Beverages, I purchased the parts and wound a couple of transformers intending on installing one or more. I then realized not only would it not fit on my lot, it would have to cross TWO neighbor's yards, and run directly under my 160 dipole. Now I have some really great neighbors, who tolerate my radio addiction, but installing wires about head high in their yards, which they regularly mow and care for, might be pushing it just a little much. I tabled the Beverage installation.

A few months later, N5LSP mentioned he was considering a K9AY loop. I did lots of reading and found that while usually not as good as a Beverage, it is FAR better than no RX antenna.

I looked at commercial units, and decided since I have all the tools needed for fabrication, I'd just build my own. While it isn't a magic, super selective antenna, mine does show about 5-6 S units difference in F/B. The F/B does seem to vary based on distance, and as expected, it shows more selectivity on 160 than on 80. Moreover, it really does drop the noise more than signals, so I am quite pleased with it.

I installed a 4X4, as a base. The vertical support is 6 sections of 48" long military fiberglass mast. Since my wife sometimes mows, I opted to NOT have "tent stakes" at the corners, so the bottom pieces are 3/4" PVC, which pivot at the base. In about 30 seconds, I can stand them all vertical, snapping them into clips screwed to the 4X4. So rather than a 30' diameter obstruction, it becomes about 6" square. After mowing, they simply drop back into place.


      Views of connectors on home brewed external switching box


9:1 binocular transformer, loop switching relays and termination 

resistors all mounted on perfboard


                    LED board                                        Initial LED testing


            finished control box                            Completed loop