Ok...I answered my own question. A deeper search on the net turned up the product.
'Clip on' EMI filters have been around for a long time. They are ferris magnets (typicaly half circles) in an plastic carrier that opens, to clip onto a cable. They are barrel shaped with a hole in the center of various diamiters. The are ment to fit snug around coaxial cables.
Years ago, I had a one that attached to a telephone line. It was supposed to speed up 'old school' internet connection when we used modems. It didn't work!
I have 4 neodymium barrel magnets, each with a 70 lb pull (takes an Act of God to separate them!!). I arranged them around the cable of my Fischer F70 (know for being EMI sensitive). I arranged them at several positions, and found ZERO difference.Nothing!
Before I poo-poo the idea, if you know something about HOW magnets minimise EMI, or if you've had a different experience, please post!