Apropos the recent discussion about TEMPEST shielding, there's an interesting product that might prove quite useful: CAPCON EMI suppressant tubing. A colleague got a shipment of it today. It's ordinary black rubber tubing that has been loaded with iron oxide. It comes in 26 sizes from .04" ID to 1.25" ID, and is claimed to have much better attenuation than ferrite beads, especially at UHF and microwave frequencies. You can shield entire cable lengths with it, or you can apply it in short segments (1" to 1') just like ferrite beads and get plenty of attenuation for less cost and weight (this stuff is *heavy*, and the 1/2" stuff cost several dollars per foot.) It's also available as sheeting in various thicknesses for lining cabinets, etc. I got the bright idea to test the absorptivity claims for this stuff by putting an 8" piece into a microwave oven. After 10 seconds, it was too hot to handle. I'd say it's doing just what it's supposed to do. Contact info: Capcon, Inc 147 W 25th St New York, NY 10001 212-243-6275 212-645-0185 (fax) Phil