Hi Kevin,
Truly a frustrating problem. RF interference is one of the most maddening problems hams encounter. suggestions, some art, some science Get on e-bay and get some very long VGA extension cords, a wireless mouse/keyboard or buy some very long extensions and move the PC 6-8 feet, or more, away from the shack/antennas/coax. RF fields decay at inverse log of distance. Since really, all of the motherboard and power supply designs are essentially the same these days, you need to focus on case, in first iterations of this. Go to Fry's or other similar stores and replace the PC case with a heavier duty steel case, with fewer openings, which is the expense of $50-80 and the effort of rebuilding the case. But RF will come out of any wire or any open hole. Ferrite beads make a small, but incremental difference on all cable coming close to the hamshack. In my case, the problem was the VGA cables since there is a lot of switching of TTL coming through the cables, but, unlike your situation, my noise got progressively worse when windows loaded. Next, get online or local RF store and buy some very high quality coax cable, LM-470 double shield cable or other very well shielded coax and replace everything with it. More expense of connectors etc. but worth the expense. Again, all your cables cannot use more than 20 feet of cable and at $1-2/foot, not a huge expense Obviously, just my opinions. RF is an art form, not a science. I am sure others will have more scientific suggestions, Michael K3MH Michael Hatzakis, Jr MD Physical Medicine and Rehabilitation Owner and Medical Director Rehabilitation Options of Issaquah 1495 NW Gilman Blvd Suite 4, Issaquah, WA, 98027 "Team approach to treatment of back and neck pain, sports and workplace injuries" 425-394-1200 Ph 425-394-0100 Fax m...@hatzakis.net http://www.rehabissaquah.com _____ From: digitalradio@yahoogroups.com [mailto:digitalra...@yahoogroups.com] On Behalf Of Gmail - Kevin, Natalia, Stacey & Rochelle Sent: Wednesday, September 23, 2009 9:42 PM To: digitalradio@yahoogroups.com; win...@yahoogroups.com Subject: [digitalradio] I Hate Computers and Radio!!!! Interference. HI All, I have been trying for the past week to get my radio quiet from the computer noise, WITHOUT any luck. The computer is a ASUS P5B Deluxe P4-3Ghz w 2.5G of ram, and 3 H/Ds with just under 1TB of space. I have an onboard Sound-card, but I brought a SignaLink-USB which arrived last week for digital modes. I am running Win7 RC (far better then Vista and even lets me run 3 monitors(handy for HRD), which by the way are not causing the noise tested them by switcvhing them on/off and did not interfer with the radio) I believe the power supply in the case is causing the problem because when I turn it on (before any software loads) the radio generates a S7 noise level on 80 and 40, a little better on 20 and above, but still there. Currently it's a waste of time even trying to listen for any digital traffic on 7080, 14.070/112 a bit better. Was even going to try WINMOR, but from what I have been reading I had better get the best RX I can first. I have tried another computer and even though it did generate some noise there, it was bareable with about an S2. As of yet I have not tried another power supply as this would require me to buy a new one (wife might get a bit upset about that one), I could pull one out of a spare computer but it's not as big as the one I have. I am about to do some googling to see if there is any mods on quieting the RF from them. Is there an easy; simple way to making this DAMM computer quieter???? Any ideas would be a help. Regards Kevin, ZL1KFM. It is coming in through the antenna because when I unscrew the coax from the radio the noise disappears.
