As my good friend George AA7JV used to say Noise I UP! I live is a city lot, 20 years ago it was in a rural area, now it is in the city, The man made noise is exponentially going up. In 2006 I bult a vertical WF with great directivity, FPL , our local power and light company did and does a great job fixing power light noise. I had a good time enjoying it, big problem was Plasma TV, but it is gone now replaced with new OLED or equivalent screens. 2010 I built a horizontal HWF, the idea was to use polarization as a filter, manmade noise propagates only vertically polarized. I can check my notes comparing both antennas and at the beguine their were even, after 5 more years the vertical WF become useless due the amount of manmade noise. Now, the main problem here are solar panels and EV. Electrical vehicles are very noise but not a problem on the, when the get home and the owner plug the charger into a big power supply the noise become an issue form 500kHz to 30 MHz, every 100 kHz there is a cluster of noise. 1800, 1900, 2000 etc.;. Two EV generate two clusters but close together, not exactly on topo of each other. Solar panel noise goes always after Sun Set. Another "thing" growing up is noise from indoor LED growing plants lamp. These are really a big problem here on 14 MHz and 3.5MHz.
My point is the we need new solutions to fight noise. My horizontal HWF is at its limit here. Just polarization filter is not enough anymore , It was necessary to detune the tower holding the HWF. The HWF at 60 FT with a 43db gain preamp was generation s6 to s7 on the S-meter with 600 Hz BW CW. After detuning the tower the noise is now s0, with some switching noise that the NB can remove it. The keep with noise going up, we need to take some difficult actions to avoid common mode noise. Doing the same is not working anymore. This video was made for a friend to see the test of the HWF at 60FT , not a good production, but give the idea how it works. https://youtu.be/IyXXFkuPZZQ 73's JC N4IS _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
