I got a laugh out of finding out so many people who "know" radio stuff, never heard of the microwave screen thing, except Hc714. I cheated though, when I still drove truck, I had a pickup at the Amana plant over in Iowa one time, and asked one of the people there what it was that stopped the radiation. And got a dumbed down explanation about waves. I mean, who knew?
Snap on Ferrites were one of the first things I bought, even before I got the big black box. I have them everywhere around my desk, and most wires have them on each end and the longer ones, in the middle. Also all the coax jumpers and antenna lead. I did this from fear of bleed over on my neighbors and them complaining to the Camp Nazi. We are not allowed outside antennas here and I do have a dipole up out there, which he hasn't seen yet. LOL
Of course, there is nowhere to put them on the mouse or keyboard, but I have doubled up on the USB fed wireless antenna transceiver. What it boils down to is, the screen was a last resort. I find the wireless stuff to valuable in my paying work to switch back. [I even ordered a new wired keyboard and mouse from Newegg, and it should be here today.] Now it will be my backup, cause this screen works so good and it's not that much trouble, that I will keep using it. When I get a meter that can read the RFI, I might find that this even reduces the radiation I am getting.
Everything is grounded, physically. I have a 5' surplus military helicopter grounding one inch wide and silvered ribbon going from the radio ground, the power supply, and the amp, and out the window to a 20' buried iron pipe. I couldn't think of anything else to do.
I have tested the screen by putting the mouse and keyboard right up against the screen and with the radio and amp turned on, I key up and nothing. No interference, nor any from the keyboard or mouse back into the radio. Short of getting that RFI meter, all I can say is, it works.