Mail Archive Search: <+subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*\[RFI\]\s+Old\s+wives\s+tail\,\s+or\s+true\?\s*$/>

Results:

References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*\[RFI\]\s+Old\s+wives\s+tail\,\s+or\s+true\?\s*$/: 22 ]

Total 22 documents matching your query.

1. [RFI] Old wives tail, or true? (score: 1): Author: Dave Cole <dave@nk7z.net>; Date: Wed, 7 Apr 2021 19:38:50 -0700; Hi, I have heard from several folks here, and elsewhere that one can gauge the amount of common mode noise on their coax by unscrewing the shield, at the radio, and leaving the center in place, while; /archives//html/RFI/2021-04/msg00030.html (6,833 bytes)
2. Re: [RFI] Old wives tail, or true? (score: 1): Author: Jim Brown <jim@audiosystemsgroup.com>; Date: Wed, 7 Apr 2021 22:36:10 -0700; No. With the shield disconnected, the antenna is different -- if there's an effective choke at the top, it's now a long wire ending at the choke, because the shield and the center are capacity-couple; /archives//html/RFI/2021-04/msg00032.html (7,190 bytes)
3. Re: [RFI] Old wives tail, or true? (score: 1): Author: Dave Cole <dave@nk7z.net>; Date: Thu, 8 Apr 2021 04:45:53 -0700; Thanks Jim!! 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist, RFI ARRL Asst. Director, NW Division, Technical Resources No. With the shield disconne; /archives//html/RFI/2021-04/msg00033.html (7,771 bytes)
4. Re: [RFI] Old wives tail, or true? (score: 1): Author: David Gottschalk <dave@highredline.com>; Date: Thu, 8 Apr 2021 09:01:58 -0400; Interesting, I wondered about the validity of this "test" So really the only way to know for sure if you have common mode noise on the coax, is to put a filter in place? 73, David KN4ZKT ____________; /archives//html/RFI/2021-04/msg00034.html (8,323 bytes)
5. Re: [RFI] Old wives tail, or true? (score: 1): Author: Dave Cole <dave@nk7z.net>; Date: Thu, 8 Apr 2021 06:46:48 -0700; ....and look for a reduction in noise. That is what the data now suggests. 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist, RFI ARRL Asst. Director,; /archives//html/RFI/2021-04/msg00035.html (8,774 bytes)
6. Re: [RFI] Old wives tail, or true? (score: 1): Author: Alan Higbie <alan.higbie@gmail.com>; Date: Thu, 8 Apr 2021 08:35:31 -0600; In 2019 K3LR presented such a test at the Dayton Contest University. Tim describes it @ 15:30 into the presentation. Here is the YouTube link: https://www.youtube.com/watch?v=wd5B5qPHI_U The relevant; /archives//html/RFI/2021-04/msg00036.html (10,000 bytes)
7. Re: [RFI] Old wives tail, or true? (score: 1): Author: Joe <nss@mwt.net>; Date: Thu, 8 Apr 2021 10:34:03 -0500; Correct Jim! This is an old trick for those that have zero room for a 160 meter antenna. We often did this and loaded the whole shebang to be able to get on 160. Joe WB9SBD No. With the shield discon; /archives//html/RFI/2021-04/msg00037.html (8,306 bytes)
8. Re: [RFI] Old wives tail, or true? (score: 1): Author: Jim Brown <jim@audiosystemsgroup.com>; Date: Thu, 8 Apr 2021 11:54:47 -0700; The fundamentals of how antennas and transmission lines work combined with the proliferation of noise sources both in our own homes and those of our neighbors tells you that there will be common mode; /archives//html/RFI/2021-04/msg00038.html (8,253 bytes)
9. Re: [RFI] Old wives tail, or true? (score: 1): Author: Jim Brown <jim@audiosystemsgroup.com>; Date: Thu, 8 Apr 2021 12:01:31 -0700; I did something similar when I owned a wood frame 2-flat on a residential lot in Chicago. I had an 80M dipole that was inductively loaded to fit between my skyhooks, and matched well on 40. I fed it; /archives//html/RFI/2021-04/msg00039.html (9,948 bytes)
10. Re: [RFI] Old wives tail, or true? (score: 1): Author: alex@kr1st.com; Date: Thu, 08 Apr 2021 15:20:44 -0400; Let me challenge that test because I'm not convinced that the test is valid. I watched that video and it only shows the signals before and after the choke has been applied, on the outside of the coax; /archives//html/RFI/2021-04/msg00040.html (9,591 bytes)
11. Re: [RFI] Old wives tail, or true? (score: 1): Author: "Tim Duffy" <k3lr@k3lr.com>; Date: Thu, 8 Apr 2021 23:45:34 -0400; Hello Alex, I can tell you that this test opened my eyes to how noise is propagated to our radio receivers. Like K9YC, W1HIS and many others I have embraced these findings. There is a reason the nois; /archives//html/RFI/2021-04/msg00047.html (10,808 bytes)
12. Re: [RFI] Old wives tail, or true? (score: 1): Author: David Eckhardt <davearea51a@gmail.com>; Date: Fri, 9 Apr 2021 17:19:49 +0000; I see we can attach something to email within this group. Therefore, please see the attachment. My antennas are deployed in a relatively RF quiet area well outside cities and in the county where I do; /archives//html/RFI/2021-04/msg00048.html (13,935 bytes)
13. Re: [RFI] Old wives tail, or true? (score: 1): Author: Jim Brown <jim@audiosystemsgroup.com>; Date: Fri, 9 Apr 2021 11:04:08 -0700; Sorry, we cannot. So, one afternoon on a whim, I made a test first with the CMC inline and then w/o CMC on my parallel conductor transmission line to / from my 450-foot long double. Losses can get qu; /archives//html/RFI/2021-04/msg00049.html (12,392 bytes)
14. Re: [RFI] Old wives tail, or true? (score: 1): Author: David Eckhardt <davearea51a@gmail.com>; Date: Fri, 9 Apr 2021 19:08:59 +0000; Losses can get quite high in a common mode choke in a line that is mismatched to it's load. Count on destructive failure with high power. Yes, the average chokes embodied in the average amateur marke; /archives//html/RFI/2021-04/msg00050.html (19,050 bytes)
15. Re: [RFI] Old wives tail, or true? (score: 1): Author: Larry K4AB <larry.k4ab@gmail.com>; Date: Fri, 9 Apr 2021 15:14:39 -0500; Hello Tim and all, What's the reasoning behind placing the choke at the amp output as opposed right at the transceiver? 73, Larry K4AB _______________________________________________ RFI mailing list; /archives//html/RFI/2021-04/msg00051.html (12,863 bytes)
16. Re: [RFI] Old wives tail, or true? (score: 1): Author: "Tim Duffy" <k3lr@k3lr.com>; Date: Fri, 9 Apr 2021 16:45:20 -0400; Hi Larry You could certainly put it at the radio however in my installation it is much more convenient to install it at the last device before the antenna feedline. My interconnecting cables going fr; /archives//html/RFI/2021-04/msg00052.html (12,825 bytes)
17. Re: [RFI] Old wives tail, or true? (score: 1): Author: alex@kr1st.com; Date: Fri, 09 Apr 2021 16:53:19 -0400; Hi Tim, My point is that the test in the video shows that a RF resistor works as a RF resistor, nothing else. It's proving Ohm's law. It doesn't show the effect on the receiver, yet it makes a claim; /archives//html/RFI/2021-04/msg00053.html (12,831 bytes)
18. Re: [RFI] Old wives tail, or true? (score: 1): Author: Wes Stewart via RFI <rfi@contesting.com>; Date: Fri, 9 Apr 2021 20:57:52 +0000 (UTC); I'm sorry, I can't help myself... Wes N7WS 73, Jim K9YC _______________________________________________ RFI mailing list RFI@contesting.com http://lists.contesting.com/mailman/listinfo/rfi _________; /archives//html/RFI/2021-04/msg00054.html (10,341 bytes)
19. Re: [RFI] Old wives tail, or true? (score: 1): Author: David Eckhardt <davearea51a@gmail.com>; Date: Fri, 9 Apr 2021 21:56:00 +0000; The input of the L-Network matching network is common mode. The output of the matching network is common mode. The common mode choke belongs at the matching network output which is common mode and te; /archives//html/RFI/2021-04/msg00055.html (14,349 bytes)
20. Re: [RFI] Old wives tail, or true? (score: 1): Author: David Eckhardt <davearea51a@gmail.com>; Date: Fri, 9 Apr 2021 22:07:15 +0000; Who wrote EMC guru"? It wasn't me!!!! I just stated at the end that I had taken the referred Henry Ott courses at HP's expense and the Howard Johnson's 4-day course at the expense of StorageTek. I do; /archives//html/RFI/2021-04/msg00056.html (11,585 bytes)

Current List: 1 - 20
Page: [1] [2]