I get mine from PE too. I've found them to be useful on power cords. They do help supress EMI/RFI. Don't expect miracles from heaven, but every bit helps. Every guitar amp I build or refurbish gets one, as stage lights, etc. can be very noisy.Roypercy said:Hi allarts Express sells these things cheap, that clamp onto your AC cord (or interconnect, I guess) and supposedly help with RF interference? Useful cheap tweak, or snake oil? Thanks for any insight
Roy
The technical name for such a core is a "balun," and YES, they do "work". What they do is basically prevent the wire they are put on from acting like an antenna. [Technically not 100 percent, but close enough to it.] :headscrat
Hyperion wrote:The technical name for such a core is a "balun," and YES, they do "work". What they do is basically prevent the wire they are put on from acting like an antenna. [Technically not 100 percent, but close enough to it.]
These posts from our two good friends point to what IMHO is an example of how sometimes a very simple device quickly becomes the subject of a very complicated discussion of physics. When I attempted to dive into this stuff on the internet, the found that the subject became opaque after the first paragraph or so. That was when the maths started. [Sigh ... around the time mastodons had just left footprints, I taught myself up to the crib level and then .... poof!]Not quite true... a "balun" (derived from "balanced" & "unbalanced") is actually a device - very often a transformer, sometimes with a ferrite core, to convert a balanced signal to unbalanced signal or vice-versa.