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References: [ +from:W4EF@dellroy.com: 302 ]

Total 302 documents matching your query.

221. Re: Topband: F connector question (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Fri, 20 Nov 2009 22:36:04 -0800
It is certainly true that 50 ohm N and 75 ohm N connectors are NOT physically interchangible (a N-50-male with trash a N-75-female). I don't recall for sure about 50 and 75 ohm BNC. The 75 ohm BNCs I
/archives//html/Topband/2009-11/msg00392.html (9,933 bytes)

222. Re: Topband: N7UA Does It Again! (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Tue, 01 Dec 2009 05:23:40 -0800
I was at my remote site north of Los Angeles goofing around this year (I have some low inverted V's hung for 80, 40, 20 and 15). The only 160 antenna I have up right now is a single 20' tall top-load
/archives//html/Topband/2009-12/msg00004.html (8,055 bytes)

223. Topband: V55DLH Question (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Mon, 07 Feb 2011 13:07:53 -0800
I noticed that DK7PE has a note one this webpage stating that he WON'T be able to join the V55DLH expedition to Namibia. All the other operators on the V55DLH website are listed as either "digital" o
/archives//html/Topband/2011-02/msg00073.html (6,892 bytes)

224. Re: Topband: LINEAR vs TOP LOADING (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Sat, 23 Apr 2011 22:26:44 -0700
Perhaps the reason was mechanical. At some point depending on the current distribution, an additional improvement in unloaded Q of the loading coil will provide diminishing returns in terms of effici
/archives//html/Topband/2011-04/msg00108.html (8,828 bytes)

225. Re: Topband: 160 metre vertical with 'top loading' (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Mon, 25 Apr 2011 23:33:20 -0700
I really don't understand why this is obfuscating, Yuri. For instance, I just modeled a base-loaded 60ft vertical in EZNEC at an operating frequency of 1825 KHz. According to the model, I would need
/archives//html/Topband/2011-04/msg00125.html (13,841 bytes)

226. Re: Topband: 160 metre vertical with 'top loading' (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Wed, 27 Apr 2011 06:26:45 -0700
A matched low-loss transmission line has distributed capacitance to ground (i.e. x number of pf/foot), but yet it does not have an appreciable current taper. Only when you introduce an open circuit a
/archives//html/Topband/2011-04/msg00147.html (11,723 bytes)

227. Re: Topband: Proper Decorum On The "Gentleman's Band"... (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Thu, 09 Feb 2012 12:04:43 -0800
Yes, the response to bad behavior seems to be more bad behavior. Sometimes the response to QRM is 10x as bad as the QRM. Sometimes a polite and directed response can be constructive (as in "EF up" if
/archives//html/Topband/2012-02/msg00073.html (9,084 bytes)

228. Re: Topband: KQ0B (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Fri, 01 Jun 2012 11:58:42 -0700
Sorry to hear that, Price. Back when I was more active, I remember Mike as being a perennial presence on the "Lowband Chat". He was a very enthusiastic lowband DXer. RIP Mike W4EF....................
/archives//html/Topband/2012-06/msg00016.html (7,226 bytes)

229. Re: Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Wed, 03 Oct 2012 11:11:31 -0700
I have long had a suspicion that some fraction of the power in surface wave must be "converted" to skywave as the surface wave encounters discontinuities in the ground medium (both physical geometry
/archives//html/Topband/2012-10/msg00160.html (11,117 bytes)

230. Re: Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Thu, 04 Oct 2012 10:33:20 -0700
Hi Dick, I get that at any point in the far field there is RF current in the ground due to the space wave from the transmitter reflecting obliquely off ground. I was, however, under the impression th
/archives//html/Topband/2012-10/msg00172.html (12,751 bytes)

231. Re: Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Tue, 09 Oct 2012 06:14:11 -0700
It will be seen from the data that no "notch" exists in the fields radiated by the monopole at elevation angles of 3 degrees and less, as expected by some when considering only the far-field patterns
/archives//html/Topband/2012-10/msg00203.html (11,921 bytes)

232. Re: Topband: Near Field/Far Field (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Fri, 12 Oct 2012 21:15:32 -0700
If you look at Ken Norton's paper from the December 1941 Proceedings of the IRE "The Calculation of Ground-Wave Field Intensity Over a Finitely Conducting Spherical Earth", he lays out the equations
/archives//html/Topband/2012-10/msg00235.html (15,925 bytes)

233. Re: Topband: Skywaves from Monopole Surface Waves (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Sat, 13 Oct 2012 20:58:57 -0700
Is the disagreement about how useful the really low angles are, or is the disagreement about if a low angle measurement (groundwave) is meaningful in determining changes in radiation at useful higher
/archives//html/Topband/2012-10/msg00239.html (12,977 bytes)

234. Re: Topband: PT0S (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Mon, 12 Nov 2012 08:13:29 -0800
I'll name names. Last night on 80 meters, K0MN kept calling over and over through the entire period (~15 minutes) when PT0S was listening for JAs at his sunrise. To make matters worse, somebody decid
/archives//html/Topband/2012-11/msg00136.html (10,383 bytes)

235. Re: Topband: PT0S (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Mon, 12 Nov 2012 08:21:52 -0800
I should add that in fairness to K0MN, I don't know if that was actually him calling PT0S or someone bootlegging his call. I've seen at least one case (and I am sure there have been plenty of others)
/archives//html/Topband/2012-11/msg00137.html (11,449 bytes)

236. Re: Topband: Outing The Scofflaws... (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Mon, 12 Nov 2012 09:27:01 -0800
For illegal power, there is not much you can do unless, as you say, you are in the shack watching it. For bad operating you can diplomatically mention to the offender that your heard someone using th
/archives//html/Topband/2012-11/msg00141.html (10,583 bytes)

237. Re: Topband: Outing The Scofflaws... (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Mon, 12 Nov 2012 10:03:43 -0800
Good advice, Mike. In fact, that's why I followed up my initial post with the suggestion that I had know way of knowing that the previously named offender was the actual perpetrator of the bad operat
/archives//html/Topband/2012-11/msg00145.html (9,374 bytes)

238. Re: Topband: Fw: "Outing the Scofflaws" - Getting Old (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Mon, 12 Nov 2012 13:57:50 -0800
I understand what you are saying, Bruce, but we should remember that other DXers may not be the only ones listening: http://pt0s.com/about.html If you read this you will see that the folks who put th
/archives//html/Topband/2012-11/msg00152.html (10,855 bytes)

239. Re: Topband: ZL9HR (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Sun, 25 Nov 2012 16:43:11 -0800
Here is what I found, Steve: http://k3el.wordpress.com/dx/zl9hr/propagation/ "2. Operating times -- It is a condition of our operating permit that we leave the island during the hours of darkness. Th
/archives//html/Topband/2012-11/msg00383.html (8,773 bytes)

240. Re: Topband: ZL9HR (score: 1)
Author: Michael Tope <W4EF@dellroy.com>
Date: Sun, 25 Nov 2012 20:32:16 -0800
Steve, et al: I also found this blurb on K3EL's blog: http://k3el.wordpress.com/ "One of the conditions of our landing permit is that we are off-island during the hours of darkness we will return to
/archives//html/Topband/2012-11/msg00388.html (9,953 bytes)

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