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1. Re: [RFI] flourescent light (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Sun, 29 Nov 2009 16:59:15 -0800; As others have correctly noted, this noise is being radiated by the power wiring and picked up by your antenna. The ONLY place to kill this noise is AT THE SOURCE, either by replacing the noise gener; /archives//html/RFI/2009-11/msg00048.html (8,111 bytes)
2. Re: [RFI] Electric blankets (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Wed, 18 Nov 2009 09:11:01 -0800; See measured data in my RFI tutorial for multi-turn chokes wound on on. For 40M, #31 or #43 are the weapons of choice. http://audiosystemsgroup.com/RFI-Ham.pdf 73, Jim Brown K9YC ____________________; /archives//html/RFI/2009-11/msg00043.html (7,072 bytes)
3. Re: [RFI] Portable ~$50 AM/SW radio for dfing? (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Mon, 09 Nov 2009 10:45:51 -0800; I STRONGLY recommend the vintage GE Super Radio. Do NOT buy the knock-off version of this radio after Thompson bought the rights and put the RCA name on it -- while it LOOKS the same, it is a greatly; /archives//html/RFI/2009-11/msg00020.html (8,361 bytes)
4. Re: [RFI] 160m-5mhz noise? (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Fri, 06 Nov 2009 08:09:46 -0800; It isn't, of course, but with the FCC deregulated, understaffed, and underbudgeted, the crooks get away with it. A big thank you to small government. 73, Jim K9YC ____________________________________; /archives//html/RFI/2009-11/msg00010.html (7,965 bytes)
5. Re: [RFI] 160m-5mhz noise? (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Thu, 05 Nov 2009 22:56:39 -0800; Yes, if you're the designer and manufacturer. There's considerable detailed design advice in Henry Ott's new book. But a nasty twist -- boards are built and EMC tested with suppression components, bu; /archives//html/RFI/2009-11/msg00004.html (7,208 bytes)
6. Re: [RFI] 160m-5mhz noise? (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Thu, 05 Nov 2009 17:37:04 -0800; One strong possibility is a switching power supply for lighting, a battery charger, or other appliance. You probably have a portable AM radio, and the top of that band is just below 160M. Find a freq; /archives//html/RFI/2009-11/msg00001.html (6,820 bytes)
7. Re: [RFI] RF quiet UPS? (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Wed, 28 Oct 2009 15:50:22 -0700; How did you test them? No "standby" UPS is likely to make noise when it's plugged in and only monitoring the line in standby mode. The noise will be generated when power has failed and it's regenerat; /archives//html/RFI/2009-10/msg00049.html (8,030 bytes)
8. Re: [RFI] RFI suppression in alarm system (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Thu, 22 Oct 2009 17:36:26 -0700; John, Are these common mode chokes or differential mode chokes? You can easily wind your own common mode chokes to cover three harmonically related ham bands by winding the right number of turns arou; /archives//html/RFI/2009-10/msg00042.html (8,104 bytes)
9. Re: [RFI] Plasma TVs vs LCD TVs (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Wed, 14 Oct 2009 09:31:45 -0700; I've also seen many positive reports here on Sony LCDs, and I've never seen a negative one. I have no issues with my Sony XBR LCD. Like Kelly, I run legal power on all HF bands and I do a lot of weak; /archives//html/RFI/2009-10/msg00037.html (6,892 bytes)
10. Re: [RFI] Maytag - Need quick answers - How can I tell the good ones (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Tue, 13 Oct 2009 18:41:27 -0700; Distance from your RIG doesn't matter. Distance from your ANTENNAS is what matters. 73, Jim Brown K9YC _______________________________________________ RFI mailing list RFI@contesting.com http://lists; /archives//html/RFI/2009-10/msg00031.html (8,461 bytes)
11. Re: [RFI] Plasma TV's (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Sat, 10 Oct 2009 18:52:29 -0700; then Hi Mike, If this stuff is radiated common mode on the audio, video, and power cables (or even the antenna cables) you can kill it by winding each cable several turns around toroids. If 20M is yo; /archives//html/RFI/2009-10/msg00020.html (8,120 bytes)
12. Re: [RFI] elevator noise (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Sun, 27 Sep 2009 11:46:55 -0700; See the discussion of variable speed motor drives in http://audiosystemsgroup.com/RFI-Ham.pdf The likely cause of the problem is radiation from current flowing in a loop between the motor and the mot; /archives//html/RFI/2009-09/msg00071.html (7,110 bytes)
13. Re: [RFI] [Elecraft] OT: Maytag Bravos RFI (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Thu, 24 Sep 2009 09:42:51 -0700; washing machine, aside from the terrible interference it put on HF, she was not happy with the rinse cycle, it was leaving soap in our cloths -and- they were not getting clean. tried and true convent; /archives//html/RFI/2009-09/msg00060.html (8,559 bytes)
14. Re: [RFI] rf current meter and ferrites (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Tue, 22 Sep 2009 13:52:07 -0700; It's a bit more complicated than that. Study my tutorial on ferrites and RFI. http://audiosystemsgroup.com/RFI-Ham.pdf The short answer is that the cable you're putting the ferrite choke onto is an a; /archives//html/RFI/2009-09/msg00058.html (8,345 bytes)
15. Re: [RFI] my screen turns on and off (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Fri, 11 Sep 2009 09:26:57 -0700; Study the tutorial below to understand the fundamental concepts, then look carefully at your antenna system and the hookup to the video screen to see how RF might be coupled into the unit, and how it; /archives//html/RFI/2009-09/msg00044.html (7,973 bytes)
16. Re: [RFI] RFI Quiet Washing Machine (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Tue, 08 Sep 2009 21:44:30 -0700; Before you rush out and buy one, it should be noted that this brand regularly appears at the bottom of Consumer Reports ratings for reliability. :) We inherited one of their dishwashers in the house; /archives//html/RFI/2009-09/msg00036.html (6,840 bytes)
17. Re: [RFI] Washer RFI/EMI (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Tue, 08 Sep 2009 21:41:13 -0700; Until about four years ago, the GE Super Radio was a very nice AM receiver. I own three of that vintage. Then it got sold off to Thompson (owner of the RCA brand), who turned it into a piece of junk.; /archives//html/RFI/2009-09/msg00035.html (8,630 bytes)
18. Re: [RFI] Washer RFI/EMI (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Mon, 07 Sep 2009 08:26:15 -0700; Lobbying by business! Money talks. And a philisophy that government is too big. And the ARRL was asleep at the switch. BTW -- another component of increased noise on the AM broadcast band is IBOC --; /archives//html/RFI/2009-09/msg00027.html (10,680 bytes)
19. Re: [RFI] Washer RFI/EMI (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Mon, 07 Sep 2009 08:13:17 -0700; I agree that considerable caution is a good thing, but I don't agree that you should not touch it. It is certainly reasonable to begin with a small capacitor value and increase it while watching the; /archives//html/RFI/2009-09/msg00026.html (9,213 bytes)
20. Re: [RFI] Washer RFI/EMI (score: 1): Author: "Jim Brown" <jim@audiosystemsgroup.com>; Date: Sun, 06 Sep 2009 21:55:14 -0700; Remember that a line filter only kills trash coming out the power cord. If the unit is not well shielded (I believe Chris said some he tested are not), you WILL need to deal with the VFD circuit. One; /archives//html/RFI/2009-09/msg00023.html (9,096 bytes)

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