Ferrite Beads for RF Interference for Wah

[defaced]

Thanks for the "how it works" explanation.  That gives me some context when reading things about the basics. 

As for design documentation, welcome to the deep end.

That seems to be a common theme when electrons and magnetic fields play together.

[amptramp]

Electromagnetic Compatibility (EMC) design is the closest thing in electronics to a black art.  I attended one of the Don White courses on filtering and shielding (he is the premiere purveyor of courses on all EMC topics) and the course started with a test to see how much we knew and more importantly, what we thought we knew that was wrong.  Not much of the first and a lot of the last.  Keep in mind, the attendees were all degreed engineers with experience (16 years at the time for me) in the field.  The teacher was excellent and I learned a lot, but it certainly showed me that "common knowledge" can be as false as the "common knowledge" in mediaeval times that tomatoes are poisonous.

Moral of the story?  Do what works.

[PRR]

Chokes (including beads) are handy for low impedance circuits.

In hi-impedance audio such as guitar lines, a few thousand ohms in the same place will really lame the RF yet hardly affect the audio; and the "lossy" is built-in.