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Loggings => 22 & 44 Meter Band HiFER Beacons => Topic started by: circuitmike on September 22, 2025, 1614 UTC

Title: What's all that noise around 13560 kHz?
Post by: circuitmike on September 22, 2025, 1614 UTC

I'm curious why there's a band of noise from about 13559.7 to 13561 kHz. I know that's an area in which RFID readers operate, and I can even see blips there when someone in my house unlocks their phone. But there's also a steady stream of noise there, with two prominent bands. I see it on remote KiwiSDRs as well, so it's presumably not nearby QRM.

Title: Re: What's all that noise around 13560 kHz?
Post by: Prairiedog on September 24, 2025, 0835 UTC

The 13.560 band is shared among a number of radio services. Among other things, FCC Part 15 govern low power hobby communications, RFID, remote control, wireless charging devices, RF ballast for hgh eficieny lighting etc.

Most of the center-band racket, however, comes from  a class of hardware called Industrial, Scientific, and Medical (ISM) equipment operating under Part 18...mainly diathermy and materials testing. Sometimes these signals reach appreciable distances, so it's fortunate that they generally don't extend too far fron the band center.