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EMI hunting:


There aren't a lot of tools for hunting EMI. Ideally a spectrum analyzer on a directional antenna would probably
be the best tool, but it's not something everyone has or can use portably.

MFJ briefly sold one for public use. The only other option I can think of would be a tool used in industry, such
as the sniffers cable TV companies use to track down leaks in their cable distribution systems.

Right now LED lighting seems to be the greatest source of EMI commonly experienced in the city. These lights use
unfiltered buck regulators to power strings of LEDs, which function as giant antennas, to broadcast their signal
noise over a wide area. These can be difficult to track down, and are often located indoors. Cities are also
converting street lights to LED and pay no attention to the amount of noise some of them can create.

Some of us get it worse than others. A ham in my area fought with the city for a year after they installed a new
LED street light right in front of his house. Then a few years later the noise came back with a vengeance, which
turned out to be a neighbor two houses up that had just installed LED lights in his garage.


cable TV distribution line leakage sniffer


MFJ-856 directional noise finder



last updated 04/17/2025 at 11:31:22 by make_www_index.command version 2025.03.04.A