Ian White GM3SEK wrote in
:

....
you should probably read:
http://www.yccc.org/Articles/W1HIS/C...S2006Apr06.pdf
= http://tinyurl.com/qnzs3
....
However, W1HIS did get rather carried away with the project, and ended
up with ferrite everywhere! For the rest of us, the best advice is:
"When the problem goes away, then stop buying ferrite."

I saw that some time ago and did wonder if he held shares in one or more
magnetics companies!

Perhaps the need for gross suppression points to a fundamental design
issue, perhaps even an OHS issue.

But, it is a good article, it shows a range of techniques for applying
ferrites for suppression.

On a lighter note, I had a job with a telecommunications carrier some
years ago, their scope included operating a national GSM mobile network.
On my first day on the job, I received an email from one of the phone
reps offering a fold up lead and aluminium radiation shield with a
central hole about the size on an ear, which one unfolded and placed
against the head over the ear before applying the mobile phone to the
ear. I said to the guy alongside "have you checked this email, it is
pretty liberal of the company to allow customer reps to be creating FUD
(fear, uncertainty and doubt) about the safety of mobile phones". He got
on the phone and advised that they guy had already been sacked, he had
violated a condition of his employment that he not represent competitive
products, mustn't have taken 10 minutes. What do they teach business
graduates at university these days?

Owen