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Total 48 documents matching your query.

21. Re: [RFI] Noise centered around 20 meters (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Sun, 24 May 2020 09:24:48 -0700
We had persistent power line noise at N6RO for two years, and indeed it went silent whenever it rained. Eventually the PG&E guy came out and precisely located it (he was a ham, as it turned out). Ro
/archives//html/RFI/2020-05/msg00103.html (8,861 bytes)

22. [RFI] Report on 12V 750W server supplies (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Thu, 4 Jun 2020 14:49:39 -0700
Articles are floating around regarding ham applications of used 12V 62.5A servers power supplies. Theyre certainly cheap enough, under $15 on ebay, and have very good build quality and certifications
/archives//html/RFI/2020-06/msg00001.html (6,848 bytes)

23. Re: [RFI] RFI Solved After 2 Years (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Fri, 10 Jul 2020 12:36:34 -0700
I also would like to hear about any low-RFI dimmers, by any maker. (Exact model numbers, please.) The Lutron Diva that I tested is likely to cause problems on the low bands but is probably ok as freq
/archives//html/RFI/2020-07/msg00018.html (7,941 bytes)

24. Re: [RFI] RFI - A Losing Battle (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Tue, 22 Sep 2020 22:28:17 -0700
One approach that Ive used successfully with unfamiliar neighbors is to make a safety-related pitch. This is especially useful when you think the source is a lighting fixture or something like HVAC e
/archives//html/RFI/2020-09/msg00117.html (8,146 bytes)

25. [RFI] List of ferrite sources and prices (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Mon, 28 Sep 2020 21:15:07 -0700
Heres a price and stock survey on ferrite toroids and clamp-ons for ham RFI applications. I post this occasionally. Some of the entries were updated a couple months ago, others are older. Stock statu
/archives//html/RFI/2020-09/msg00197.html (14,559 bytes)

26. [RFI] RFI Report on Tripp-Lite UPS installations (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Mon, 30 Nov 2020 09:18:25 -0800
Here is a detailed report on the installation and RFI mitigation required for two Tripp-Lite UPS systems, model SU1000RTXL2UA. The basic unit supports external battery expansion units, which is the m
/archives//html/RFI/2020-11/msg00074.html (6,913 bytes)

27. Re: [RFI] Utilitech LED Recessed Lighting (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Mon, 30 Nov 2020 09:27:30 -0800
No experience or rumors about that one. Their website seems to contain zero technical info. Id be very skeptical and you should obtain one for testing before committing to any permanent installation.
/archives//html/RFI/2020-11/msg00075.html (7,997 bytes)

28. Re: [RFI] RFI Digest, Vol 214, Issue 19 (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Mon, 30 Nov 2020 11:29:42 -0800
Search on Amazon for "12v led recessed light and youll find many, sold for the RF and boat market. That looks like a really good solution, something I hadnt really thought about. Thanks to Jim for th
/archives//html/RFI/2020-11/msg00078.html (6,983 bytes)

29. [RFI] QUESTION (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Mon, 21 Dec 2020 16:48:16 -0800
Thats easy. RF is picked up on the AC lines then enters any nonlinear device plugged into those lines, such as a walk wart. There, RF is rectified, harmonics are generated, and thats mixed with all t
/archives//html/RFI/2020-12/msg00101.html (8,013 bytes)

30. Re: [RFI] RFI to Automobile Remote (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Wed, 6 Jan 2021 10:22:43 -0800
US keyfobs operate at 315 MHz. For direction finding, an HT and a hand-held Yagi for 430 MHz would probably be ideal since the offending source apparently has lots of energy in the UHF range. Put you
/archives//html/RFI/2021-01/msg00016.html (7,410 bytes)

31. Re: [RFI] Mini-Split for new ham shack (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Mon, 8 Mar 2021 18:43:39 -0800
_______________________________________________ RFI mailing list RFI@contesting.com http://lists.contesting.com/mailman/listinfo/rfi
/archives//html/RFI/2021-03/msg00009.html (9,817 bytes)

32. Re: [RFI] New Interference at kk0sd (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Sun, 21 Mar 2021 16:41:34 -0700
I agree it really sounds like arcing associated with power lines, even though yours are underground. But I had that same sonic signature here, and the root cause was a big TIG welder that a neighbor
/archives//html/RFI/2021-03/msg00063.html (8,346 bytes)

33. Re: [RFI] New Interference at kk0sd (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Tue, 23 Mar 2021 16:06:26 -0700
Resonant loops are absolutely the way to go with portable radios. My simple 80-15m design, quite similar to that of W0IVJ, is included in the extra files with the current ARRL Handbook. Many people h
/archives//html/RFI/2021-03/msg00099.html (8,549 bytes)

34. Re: [RFI] RFI in Mini-Split (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Fri, 2 Apr 2021 12:48:46 -0700
Similar question was discussed at the start of last month. http://lists.contesting.com/pipermail/rfi/2021-March/thread.html Gary NA6O _______________________________________________ RFI mailing list
/archives//html/RFI/2021-04/msg00002.html (7,101 bytes)

35. Re: [RFI] Raspberry PI / Wall wart RFI (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Fri, 2 Apr 2021 19:40:11 -0700
Yes... Apple adapters are excellent. Heres a detailed report. Other tested and recommended devices are also listed on my RFI page. http://wb9jps.com/Gary_Johnson/RFI_files/Apple_A1401_12W_USB_adapter
/archives//html/RFI/2021-04/msg00007.html (7,540 bytes)

36. Re: [RFI] LED lighting fixtures - (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Mon, 24 May 2021 12:39:52 -0700
Delightful to hear an LED light recommendation from a reliable source like Frank, who knows what hes doing and went so far as to perform a specific noise test. I will add this to my list of recommend
/archives//html/RFI/2021-05/msg00078.html (8,461 bytes)

37. Re: [RFI] SOLAR INSTALLATION PROS/CONS (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Tue, 25 May 2021 07:47:50 -0700
Search for solaredge in our archives at http://lists.contesting.com/mailman/listinfo/rfi <http://lists.contesting.com/mailman/listinfo/rfi> and you will find hundreds of posts. The company was also t
/archives//html/RFI/2021-05/msg00092.html (8,975 bytes)

38. Re: [RFI] Solar array RFI info to use to educate community group (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Sat, 5 Jun 2021 10:55:32 -0700
Heres a decent RFI article from a solar contracting company. https://www.solar-electric.com/learning-center/reducing-electromagnetic-interference-pv-systems.html/ Here is the official installation re
/archives//html/RFI/2021-06/msg00003.html (8,647 bytes)

39. Re: [RFI] What was that noise? (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Fri, 25 Jun 2021 09:29:15 -0700
I use my Ridgid drill charger as a demonstration device when giving RFI talks to clubs. It plays an almost musical sound on all HF bands, something the audience always enjoys. Then I coil up a half d
/archives//html/RFI/2021-06/msg00069.html (7,051 bytes)

40. Re: [RFI] LED Bulb RFI (score: 1)
Author: Gary Johnson <gwj@wb9jps.com>
Date: Thu, 8 Jul 2021 13:20:18 -0700
Nice work, Ken. I'm glad to see someone publishing on the subject of conducted emissions below 30 MHz. Most of the articles on RFI design engineering these days focus on radiated emissions and much h
/archives//html/RFI/2021-07/msg00031.html (9,470 bytes)


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