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41. [TenTec] Re: " A Low vswr will kill you !" (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 09:43:03 -0600; 3/4" spaced line radiates at 6m. Enough to cause local TVI and to change beam patterns and to hear local noise. Back in the days when it was written that it didn't radiate, receivers had NF > 10 dB,; /archives//html/TenTec/2001-01/msg00485.html (7,675 bytes)
42. [TenTec] Re: grounding, station plug in protection (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 11:46:53 -0600; A single point disconnect that involves antenna, phone, and power, I believe is a BAD idea. Because if its metal, it leaves the POWER ground connected to the ANTENNA ground and connected to the phone; /archives//html/TenTec/2001-01/msg00488.html (9,111 bytes)
43. [TenTec] Re: " A Low vswr will kill you !" (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 11:47:12 -0600; Water in Belden 9913 gives a very nice match at 440 MHz, but also makes the air insulated coax into a very effective attenuator. If a transmission system has both low SWR and proven low loss, then SW; /archives//html/TenTec/2001-01/msg00489.html (9,723 bytes)
44. [TenTec] " A Low vswr will kill you !" (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 11:57:33 -0600; Tuning through a ferrite cored balun is fraught with difficulties, which sometimes are identified by the balun core heating, sometimes by lack of signal, sometimes by the tuner heating, and sometimes; /archives//html/TenTec/2001-01/msg00491.html (7,683 bytes)
45. [TenTec] Re: grounding lightning induction to ant. (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 13:15:40 -0600; I have seen SO-239 connectors flash over the face with charged clouds passing by the antennas. The energy stored in 200 feet of RG-8 makes a loud enough snap to make one rise a foot or so when its no; /archives//html/TenTec/2001-01/msg00494.html (8,196 bytes)
46. [TenTec] "A low vswr will kill you ! " (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 17:50:41 -0600; The air core baluns are not as effective at forcing balance as the toroidal baluns, nor as tolerant for frequency or impedance ranges. They may not overheat the core but they may not accomplish the b; /archives//html/TenTec/2001-01/msg00518.html (9,849 bytes)
47. [TenTec] "A low vswr will kill you ! " (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 18:18:21 -0600; My tuner uses the parallel secondary connection that Cebek reports for some antennas and feed line lengths and the series connection for others. With 1/4" edge wound strap in the coil, its easy to co; /archives//html/TenTec/2001-01/msg00520.html (10,938 bytes)
48. [TenTec] balanced antenna systems (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 22:30:35 -0600; The fact that antennas are not guaranteed to be balanced means that a tuner that tries to force balance by grounding the center of the output coil or capacitor or the (GASP!) balun often leads to unb; /archives//html/TenTec/2001-01/msg00527.html (8,989 bytes)
49. [TenTec] "A low vswr will kill you ! " (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Tue, 23 Jan 2001 22:30:39 -0600; I guess we think about resonance in the antenna being better for radiation, but there have been "magic" easily tuned lengths (and antenna and feed) in antenna articles and handbooks ever since the us; /archives//html/TenTec/2001-01/msg00528.html (11,282 bytes)
50. [TenTec] "A low vswr will kill you ! " (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 10:30:27 -0600; Nope, just chosen to make tuning easier. Predates coax by decades. Line pickup is mostly a function of spacing and antenna balance in open wire feeders. Feeder balance is upset by the feeder not bein; /archives//html/TenTec/2001-01/msg00533.html (10,834 bytes)
51. [TenTec] "A low vswr will kill you ! " (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 10:30:24 -0600; Hertz didn't REQUIRE a resonant radiating element but that resonant radiating element was his only frequency determining element in his experiments. Radiating elements don't need to be resonant to fu; /archives//html/TenTec/2001-01/msg00534.html (10,491 bytes)
52. [TenTec] Is your message not showing up on the list? (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 10:41:31 -0600; As a counter argument to free use of RTF and HTML, there are still a number of users with text only e-mail services such as hotmail that when they receive RTF or HTML or graphics, they only receive p; /archives//html/TenTec/2001-01/msg00535.html (8,129 bytes)
53. [TenTec] "A low vswr will kill you ! " (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 13:49:00 -0600; I was referring to the mathematician, James Clerk Maxwell, not to "Look at Reflections" Maxwell. 73, Jerry, K0CQ -- FAQ on WWW: http://www.contesting.com/FAQ/tentec Submissions: tentec@contesting.com; /archives//html/TenTec/2001-01/msg00545.html (9,863 bytes)
54. [TenTec] "A low vswr will kill youo" (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 14:33:34 -0600; Thats not a proper definition. Resonance has to do with zero phase angle of impedance. A wire can end at disks with significant current and yet be resonant. 73, Jerry, K0CQ -- FAQ on WWW: http://www.; /archives//html/TenTec/2001-01/msg00548.html (8,521 bytes)
55. [TenTec] "A low vswr will kill you ! " (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 14:59:34 -0600; There is no conjugate match to the output of any active source, whether vacuum tube, or bipolar transistor, or FET. Maybe there is in traveling wave devices or modulated wave devices such as TWT and; /archives//html/TenTec/2001-01/msg00550.html (12,235 bytes)
56. [TenTec] "A low vswr will kill you ! " (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 22:38:27 -0600; I guess I started to read about leaky coaxes and skipped the rest of that article. I've learned that coax does leak, cheap coax leaks more. Gary Breed now is editor for Microwaves and RF magazine and; /archives//html/TenTec/2001-01/msg00592.html (10,340 bytes)
57. [TenTec] Power Amps, Conuugate, Bruene and Maxwell (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 22:39:21 -0600; I don't agree. The filter is a matching network as well as a filter. It supplies a suitable load impedance for the switches and power supply to develop the desired power level. 73, Jerry, K0CQ -- FAQ; /archives//html/TenTec/2001-01/msg00593.html (9,962 bytes)
58. [TenTec] Re: Power Amps, Conuugate, Bruene and Maxwell (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Wed, 24 Jan 2001 22:58:18 -0600; All Tentecs require antennas. All antennas require feedlines. All Tentec transmitters use power transistors or tubes for output devices. These two explanations are antagonistic. Maxwell ascribes a va; /archives//html/TenTec/2001-01/msg00596.html (11,137 bytes)
59. [TenTec] "A low vswr will kill you" (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Thu, 25 Jan 2001 15:55:38 -0600; Sherrill, your wish for a simplified definition of resonance and the one you wish to use is faulty. Every antenna (without disks at the ends) has zero current at the end of the wire. The antenna curr; /archives//html/TenTec/2001-01/msg00628.html (8,131 bytes)
60. [TenTec] Broad Band Antenna (score: 1): Author: geraldj@ames.net (Dr. Gerald N. Johnson, electrical engineer); Date: Fri, 26 Jan 2001 10:02:04 -0600; RIGHT ON! The B&W broadband antenna is a leaky dummy load. Might as well use any coax fed dipole with a T in the coax hooked to a 50 ohm dummy load to present a match to the radio. I recalled that re; /archives//html/TenTec/2001-01/msg00651.html (8,807 bytes)

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