At 17:07 7/22/2005, John wrote: >Video cables and I think a few other types are required by the >FCC to have RFI suppression installed. That is the little cylinder shaped >thing you see. It is a toroid core. That end of the cable connects to the >video monitor. It prevents RFI from the monitor feeding back out and using >the cable as an antenna to broadcast RFI to other electronic devices in the >area. Thanks, John. Very interesting. I searched on RFI and landed on a site all about Ham radios. <http://www.arrl.org/tis/info/rficomp.html> Wow, the stuff you didn't know you didn't know, but sorta get. I had no idea the noise from some equipment would interfere with a radio. So, the toroid core is like a filter. I'm wondering if this cable that goes from my fax machine to my computer would be of any use anywhere else? I never connected the fax to the computer. Would it work to set up a dual monitor rig? There's one of those toroid cores on one end of the cable, so I could plug the toroid cored end into a spare monitor and the non-cored end into my laptop and I'd have a dual monitor setup? Diane The NOSPIN Group has added a new feature on our website, web based bulletinboard for questions and answers: Visit our sister website at http://nospin.com