Ferrite beaded cords, and especially double-sided ferrite beaded cords, seem especially uncommon. Are there other, perhaps more effective ways, which I should be minimizing the EMI of my overcrowded workstation?

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    $\begingroup$ that depends on what kind of EMI, especially at which frequencies, you want to block, and for what your devices already internally have countermeasures.. The only "catch-all" method I'd be aware of would be not operating your workstation. $\endgroup$ – Marcus Müller Jan 11 '20 at 22:35
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    $\begingroup$ What are you trying to accomplish? It would help us if we knew what equipment was being affected by the EMI, and how. $\endgroup$ – Mike Waters Jan 12 '20 at 2:09
  • $\begingroup$ Nothing, yet, I was just looking to minimize any potential problems that may arise. I've got a lot of data cables (usb, thunderbolt, etc) around my current workstation and noticed that very few cables come with ferrite chokes. Is rfi at a workstation itself a non-issue for most ham applications? $\endgroup$ – user15628 Jan 13 '20 at 11:43
  • $\begingroup$ @begs-the-hessian no, it's not a non-issue, but if you can't narrow down what bands you want to operate, it's impossible to recommend what to do – EMI mitigation is inherently frequency-selective, so what you need to do at the very least depends on what bands you're planning to operate. $\endgroup$ – Marcus Müller Jan 13 '20 at 17:47
  • $\begingroup$ 20m and want to play around with 2.4ghz so was hoping to minimize for both, which are pretty far apart I know. $\endgroup$ – user15628 Jan 13 '20 at 20:02

First thing to do is determine the EMI source(s). Chargers for mobile devices, LED room lighting, and/or rooftop solar panels, etc., can easily generate a noise floor above that of your workstation. Neighbors can generate EMI closer to your antenna(s) than your office.

I cut the main circuit breaker to my house, and turned things on one at a time to find the worst RF noise sources. A printer in another room was one. However I found the noise floor went down even lower when there was a neighborhood wide power outage, so some of the RFI is out of my control.

For the worst random power cords, cables (USB, ethernet, video, 12V, etc.), and coax feed lines near my radio receivers, I wrapped a few to several turns (often limited by how many turns fit), thru type 31 or type 43 ferrite toroids. I saw little to no effect from using single no-name clamp-on ferrite beads, or cables that came with them (but use them anyway).


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