I believe, and I think most other shortwave listeners would agree, that the biggest problem facing our hobby today is noise, radio frequency interference (RFI) from other electronic devices.
Long Rambling Preface
Just sitting here typing on my wireless electronic keyboard, connected to a desktop PC, connected to two LED monitors, with a desk illuminated with an LED lamp, just to the right of a LCD weather station display, above a desk drawer containing an outlet strip with USB charging ports, sitting beside an AC adapter powering an 8-bay battery charger, wireless mouse, on top of a wireless PC speaker and an AC-powered Wi-Fi network extender, not to mention a smartphone, all within 3 feet of me, provides ample examples for potential for generation of RFI.
A few years back, I took three approaches to reduce the noise. I put a chair outdoors far away from the house with a 20 ft. wire up a tree antenna, I got an MLA-30+loop antenna installed at a far corner of the house with a shielded antenna lead in the window, and I went on an active search and destroy mission to find and eliminate the sources of the noise. That was because the first 2 approaches didn’t help.
The find and destroy approach had partial success. It discovered one particular device, a Nitecore D2 battery charger, that created more noise than everything else put together. It was beyond belief how bad it was, just plugged in, whether actively charging a battery or not. It saturated the whole house with noise so that the only way I could find it it was by singly turning off every breaker in the house, and once the offending circuit was found, I had to turn off and unplug every device and outlet strip until the noise stopped.
The other offending device was my electronic dog containment fence. It uses an Invisible Fence Boundary Plus® Dual Loop Transmitter to inject 10.7 kHz or 7.5 kHz signals into buried wires around the perimeter of my property. Those are high audio frequencies, not what we expect as radio. Nevertheless, the unit creates a raucous crackle on my radios everywhere between 4 and 6 MHz.
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