[edit]a note to Craig
seing my title "nope( you can not tell by the picture)" together with the previous post I realize it is totally misleading. I definitely did not mean nope, let's not get back to the topic as my post show.

If no big effort, could you makle it possible to edit the title as well as the post?[end edit]



I don't expect that you could predict the manufacturer or anything alike from the pictures :) .

nope

A few years ago when the electronic world was a bit slower we did not use any ferrites. Now that everything is faster I include them "just to be sure" and thus I can not imagine that any reputable manufacturer would have nonperforming beads. Please DO NOT misunderstand "just to be sure" that does NOT man "not needed". The fact is that you never know which and where are needed and so called "testing" would not give reliable results

I use 2 "grab bag" beads
for signal: Murata BLM21A601FPT
for current: Stewart HI1206n101-R00
both specified on the BOM as "or equivalent"

However, if I were in high performing analog, it would not be a grab bag issue.

Erik

re so called "testing"

What that expression refer to is not funtionality testing, but testing blindly if a haphazard design happen to work.

My basic attitude to testing is: if testting finds hard errors, you have made a mistake, if it finds intermittent errors, you have screwed up the design. Even worse, if your screwed up design passes the testing and the customer find the intermittent error.