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41. TopBand: Exceptional Conditions (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Tue, 9 Dec 97 09:15:12 -0500; Good conditions noted into JA from here in eastern MA this morning from 1130Z to my sunrise at 1200Z--the best conditions into JA so far this season, although the strongest signals were only 559 (on; /archives//html/Topband/1997-12/msg00147.html (7,007 bytes)
42. TopBand: cheap gamma/omega capacitors for shunt fed towers (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 1 Nov 97 09:55:30 -0500; Another viewpoint: I used to use coax stubs as capacitors but stopped doing so after I made some measurements which showed significant resistive loss (several ohms) in long stubs using RG 213. I neve; /archives//html/Topband/1997-11/msg00008.html (7,850 bytes)
43. TopBand: cheap gamma/omega capacitors for shunt fed towers (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 1 Nov 97 16:36:24 -0500; A followup to my earlier post about coaxial line capacitors: Resistive loss in coaxial stubs, used as capacitors, inductors, or whatever, is an unavoidable consequence of the attenuation present in a; /archives//html/Topband/1997-11/msg00017.html (7,856 bytes)
44. TopBand: Skewing (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sun, 23 Nov 97 07:14:49 -0500; Here in New England, we also noted skewing of the European signals during last night's (22-23 Nov.) opening. Many of the Europeans were stronger or as strong on my 135 degree Beverage as on the 45 de; /archives//html/Topband/1997-11/msg00323.html (6,935 bytes)
45. TopBand: Resonant verticals (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Thu, 14 Aug 97 11:28:21 -0400; Resonance is not a fundamental requirement for an antenna to radiate or to receive. As any antenna engineer can tell you, an infintesimally short vertical monopole has a theoretical gain within a fra; /archives//html/Topband/1997-08/msg00076.html (8,838 bytes)
46. TopBand: Why is a duct? (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Thu, 3 Jul 97 17:53:05 -0400; To elaborate further on this selectivity, I have often observed that W2's in Eastern NY and NJ usually have a huge advantage to JA over those of us here in Eastern MA, even at our sunrise. Frequently; /archives//html/Topband/1997-07/msg00014.html (7,974 bytes)
47. TopBand: Top Hat Loaded Verticals (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Wed, 30 Apr 97 17:21:37 -0400; Thanks for the plug, Carl! Actually in its first incarnation, I did use 40 foot verticals, but they are now 61 feet tall. This is still somewhat short electrically on 80, so I do use the top set of; /archives//html/Topband/1997-04/msg00151.html (9,559 bytes)
48. TopBand: 2-wire Beverages (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Tue, 25 Feb 97 14:25:54 -0500; It is my experience that Beverage antennas really do want to work and are quite forgiving of imperfect construction techniques. I have never had anything but good performance from every Beverage I ha; /archives//html/Topband/1997-02/msg00388.html (9,434 bytes)
49. TopBand: 9V1XQ on LP (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 11 Jan 97 18:54:51 -0500; I heard 9V1XQ this evening (Jan. 11) at 2230Z on 1825.8 coming through on long path. Signals peaked 569 on the southeast Beverage, and were not audible from any other direction. However, as soon as I; /archives//html/Topband/1997-01/msg00215.html (7,006 bytes)
50. TopBand: HEARD Report - Sunday PM - USA (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Tue, 21 Jan 97 10:20:12 -0500; Interesting comments from W4ZV, K8DO, et al on VK0IR propagation Sunday evening. Here in W1, they were also peaking from the northeast while at the same time they were absolutely booming in from the; /archives//html/Topband/1997-01/msg00356.html (7,509 bytes)
51. TopBand: Spurs, etc (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Tue, 10 Dec 96 10:03:08 -0500; [stuff deleted...] Carl makes a good point about the phase noise problems in the synthesized radios. I would like to add that the rigs which transmit high phase noise sidebands will also have a reci; /archives//html/Topband/1996-12/msg00167.html (9,236 bytes)
52. TopBand: VK6 on Long Path (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Sat, 14 Dec 96 17:57:04 -0500; I heard a buzz of Europeans calling something on 1826 around sunset here at 2110Z. I listened and it was VK6VZ coming through on the long path. Signals were not very strong--only about RST 449. He wa; /archives//html/Topband/1996-12/msg00249.html (6,978 bytes)
53. TopBand: Antenna coupling (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Tue, 1 Oct 96 09:54:45 -0400; There is a lot of useful information in ON4UN's Low Band DXing book in the chapter on phased vertical arrays. Also, I recommend K2BT's series of rather technical articles on phased arrays which appe; /archives//html/Topband/1996-10/msg00006.html (7,643 bytes)
54. TopBand: UA0KAG into East Coast (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Tue, 1 Oct 96 10:00:07 -0400; Hi gang, A bunch of East Coasters worked UA0KAG this morning on 1832. I heard him come up out of the noise for a few minutes around 1030Z before disappearing completely just before sunrise. I heard h; /archives//html/Topband/1996-10/msg00007.html (6,664 bytes)
55. TopBand: How many radials is enough? (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Wed, 2 Oct 96 10:23:49 -0400; In view of all the discussion on verticals and radials, I thought it would be useful to reproduce some of the radial data reported in the Brown, Lewis, and Epstein paper which Tom W8JI has cited. For; /archives//html/Topband/1996-10/msg00026.html (10,199 bytes)
56. TopBand: Beverage question (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Mon, 21 Oct 96 13:37:01 -0400; Coax lines like RG-59 can certainly be used. For very long runs, there will be more loss than for RG-213, but since you probably won't be transmitting into your Beverage, this should not be a proble; /archives//html/Topband/1996-10/msg00301.html (8,185 bytes)
57. TopBand: Inverted-L question (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Mon, 30 Sep 96 14:13:55 -0400; [stuff deleted...] These comments are essentially correct if one assumes the antenna is a standard quarter-wave vertical whose radiation resistance is theoretically around 36 ohms. However, one can m; /archives//html/Topband/1996-09/msg00267.html (10,317 bytes)
58. TopBand: Inverted-L question (score: 1): Author: kaufmann@ll.mit.edu (John Kaufmann); Date: Mon, 30 Sep 96 16:12:25 -0400; ... Actually, my choice of the 2 quarter-wave 90-degree phased verticals in the last statement above was a bad one for this example because this array has the interesting property that the gain over; /archives//html/Topband/1996-09/msg00268.html (10,937 bytes)

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