In the UK there has been a great deal of interference caused by plasma screens. The QRM is radiated by the screen and gets worse with age as the power to the backlight increases to compensate for reducing emissivity. Recently Panasonic, the main culprit, have been replacing plasmas with their latest LCD model that have much better pictures and no rfi. Current LCD models now have much improved performance and have better pictures that the plasmas that are now being phased out.
A campaign has been waged by concerned amateurs and details can be found at http://www.ukqrm.org.uk/ Best of luck 73 Peter G3SMT ________________________________ From: WM3M <[email protected]> To: Bill Hammond <[email protected]>; Elecraft Reflector <[email protected]> Sent: Friday, 5 July 2013, 17:45 Subject: Re: [Elecraft] OT P3 video of RFI, ideas? Bill, I have a 50 inch Panasonic plasma and when it is on, lower bands 40 meters and below are near useless. It causes some problems for me on 20 meters and up but it gets less as the bands go up. My P3 display is similar to yours. Otherwise it’s a great TV, great picture. I have tried several things but only thing that has helped, especially on 20 meters and above is to move ham antenna further away from my house. As best I can tell RFI comes from the screen and not the cables or the power cable. If anyone finds a better solution, other than shotgun or not using it, please let me know. 73 good luck Emory WM3M -----Original Message----- From: Bill Hammond Sent: Friday, July 05, 2013 12:29 PM To: Elecraft Reflector Subject: [Elecraft] OT P3 video of RFI, ideas? This is a bit off topic but perhaps other P3 users on this reflector have encountered this RFI and have some idea where it comes from and perhaps a remedy? There must be a couple of thousand P3 users on this reflector. The below is a recording and includes sound of this nasty bit of pulsating RF. Video recording: http://www.flickr.com/photos/ak5x/9214448105/ It is not always there. When it is there in the 20-meter band there are siblings almost as strong at the following frequencies: 13.975 14.032-the recording 14.126 14.220 14.282 14.469 In addition, there are less strong signals that follow the pulsation; one is visible on the recording at 14000 (far left on the P3). They are also in the 17 meter band. They are not in the 15 meter band or above. I have pulled the big switch and it is still there on battery power. My suspension is a neighbor with plasma television. Is this what plasma TV looks like? It is directional in nature and the strongest signal comes from a 40-degree heading, roughly Europe from my location, or to a cluster of homes to my northeast. 73, Bill AK5X Bill Hammond [email protected] Bill Hammond-AK5X [email protected] [email protected] K3 #69 P3 #817 KPA500 # 149 K2/100 #4637 K1 #2033 KX1 #1023 KX3 #583 W2 T1 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
