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References: [ +from:i4jmy@iol.it: 132 ]

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81. [TowerTalk] 20 Meter (score: 1): Author: i4jmy@iol.it (Maurizio Panicara); Date: Mon, 5 Mar 2001 23:16:49 +0100; Everything is relative. Conventional inductors are loading devices with appreciable losses if compared to full size elements and this loss is more evident in yagi arrays where the amount of the curre; /archives//html/Towertalk/2001-03/msg00109.html (9,749 bytes)
82. [TowerTalk] 20 Meter (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Tue, 6 Mar 2001 10:23:13 +0100; A 5% loss with 1500W is 75w but with amateur duty cycles the wasted energy (joule) it's practically a lot less. Expecially if considering that joints are typically in open air, mostly connected or be; /archives//html/Towertalk/2001-03/msg00118.html (13,287 bytes)
83. [TowerTalk] X-beam (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Wed, 14 Mar 2001 15:50:52 +0100; May be the following link has some interest for you and for who has not April 1960 CQ-Magazine http://www.cebik.com/bc.html 73, Mauri I4JMY either looking for Magazine gave -- FAQ on WWW: http://www.; /archives//html/Towertalk/2001-03/msg00282.html (7,668 bytes)
84. [TowerTalk] back to back yagis (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Wed, 14 Mar 2001 16:49:10 +0100; A long yagi without a F/B and a 3 db loss over the max gain is basically a nonsense, expecially at HF and for general amateur use. It's a much better idea to use two independent rotating staked yagis; /archives//html/Towertalk/2001-03/msg00284.html (10,467 bytes)
85. [TowerTalk] Re: flexible coax (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Fri, 16 Mar 2001 12:17:50 +0100; A very good (but expensive) solution is to use RG393, a double shielded teflon insulated coaxial cable similar in size to RG214. In any case (this is an idea "stolen" from VHF and UHF contesters) a l; /archives//html/Towertalk/2001-03/msg00319.html (10,882 bytes)
86. [TowerTalk] problems with 10m COMTEK 4 sq unit (score: 1): Author: i4jmy@iol.it (Maurizio Panicara); Date: Mon, 19 Mar 2001 20:00:25 +0100; Unless over an extensive ground system and avoiding to elevate the antenna from ground, a vertical array on 10m will not have a consistent energy radiated at very low angles and no signal enforcement; /archives//html/Towertalk/2001-03/msg00377.html (10,681 bytes)
87. [TowerTalk] Modeling and reality. (score: 1): Author: i4jmy@iol.it (Maurizio Panicara); Date: Tue, 20 Mar 2001 20:22:43 +0100; Modeling works fine if the software is reliable, the user knows its limitations and expecially how to write down a proper file. 73, Mauri I4JMY wunderantenna, -- FAQ on WWW: http://www.contesting.com; /archives//html/Towertalk/2001-03/msg00418.html (7,620 bytes)
88. [TowerTalk] rope in elements (score: 1): Author: i4jmy@iol.it (Maurizio Panicara); Date: Wed, 28 Mar 2001 20:21:17 +0200; Not necessarily a vibration causes a metal stress in aluminium or a failure in a riveted joint. Thousand of yagis elements are infact happily surviving and vibrating day after day (likewise aircrafts; /archives//html/Towertalk/2001-03/msg00606.html (9,959 bytes)
89. [TowerTalk] Shadowing of small antennas by larger ones? (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Thu, 1 Feb 2001 10:19:33 +0100; Hi Guy, in a multiband array using a single boom it's not an easy task to find out where to place planar and different bands elements without affecting negatively the antenna performances on one or m; /archives//html/Towertalk/2001-02/msg00002.html (11,869 bytes)
90. [TowerTalk] (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Fri, 2 Feb 2001 10:58:24 +0100; Hi Tom, isolated parasitic elements on the same boom are placed in different positions to be practically "transparent" to each other but fuctional to the belonging band, only. A parasitic open sleeve; /archives//html/Towertalk/2001-02/msg00033.html (7,279 bytes)
91. [TowerTalk] Quad vs. yagi (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Tue, 6 Feb 2001 15:51:02 +0100; Quad are mechanically prone to give troubles, and ther installation is more complex and time consuming since they are 3D antennas. Expecially with 20 meters, or worse with 40m elements, the quad boom; /archives//html/Towertalk/2001-02/msg00161.html (11,094 bytes)
92. [TowerTalk] Quad vs. yagi (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Wed, 7 Feb 2001 10:20:36 +0100; if I'm convinced the wrong Quad gain issue got enforced by a number of rough comparison between 2/3 element tribanders yagi and tribanders quad, expecially if performed on 20m. Since most manufactur; /archives//html/Towertalk/2001-02/msg00189.html (10,121 bytes)
93. [TowerTalk] re: quad (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Fri, 9 Feb 2001 12:10:52 +0100; As a matter of facts, a number of yagi antenna designs popular on the 70' and 80' were far to be really optimized, and this explains why antenna shapes (spacings, lenghts) and results of different in; /archives//html/Towertalk/2001-02/msg00237.html (10,985 bytes)
94. [TowerTalk] Dream on,he will have to prove it to manufacturers onhis de... (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Mon, 12 Feb 2001 13:25:11 +0100; Antenna modeling, at least to determine maximal gain (phisical of the array) is more accurate than any test environment. A test environment is a useful tool when all the external parameters are under; /archives//html/Towertalk/2001-02/msg00321.html (10,235 bytes)
95. [TowerTalk] Elevated Radials (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Tue, 20 Feb 2001 15:40:58 +0100; If radials are far enough from ground to really approximate an electrical counterpoise, then it's better if the counterpoise itself is symmetrical in order to decouple the antenna from the transmissi; /archives//html/Towertalk/2001-02/msg00340.html (7,651 bytes)
96. [TowerTalk] Beverage feeding (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Tue, 27 Feb 2001 10:08:22 +0100; Hi Tom, first of all a simple transformer is finally much simpler than a tuner, it's broad band, the coupling is primarily magnetical, the unit is self shielded and the required enclosure is quite s; /archives//html/Towertalk/2001-02/msg00483.html (7,823 bytes)
97. [TowerTalk] Rombic antennas better then beams??????????? (score: 1): Author: i4jmy@iol.it (i4jmy@iol.it); Date: Tue, 2 Jan 2001 10:47:06 +0100; The rhombic antenna is also a wide band aerial that may cover, of course with different performances, several bands. Unidirectionality and (some) constant impedance are also obtained terminating the; /archives//html/Towertalk/2001-01/msg00042.html (8,382 bytes)
98. [TowerTalk] Antenna proximity--problems with rx overload (score: 1): Author: i4jmy@iol.it (Maurizio Panicara); Date: Sun, 7 Jan 2001 18:07:06 +0100; PIN diodes have reciprocal mixing troubles when a saturation DC current is absent and the diode is in the conductivity region between the thresold and complete saturation. Using PIN diodes as variabl; /archives//html/Towertalk/2001-01/msg00179.html (8,394 bytes)
99. [TowerTalk] Radials over salt water? (score: 1): Author: i4jmy@iol.it (Maurizio Panicara); Date: Mon, 8 Jan 2001 23:04:52 +0100; correctly, tidal An high overall antenna efficiency is not necessarily coincident with a big GP efficiency at very low elevations. If the important point is to radiate at very low angles (below 1 de; /archives//html/Towertalk/2001-01/msg00210.html (9,436 bytes)
100. [TowerTalk] Radials over salt water? (score: 1): Author: i4jmy@iol.it (Maurizio Panicara); Date: Mon, 8 Jan 2001 23:24:14 +0100; Because with vertically polarized antennas the very low elevation angles are present only when the ground (that one extending for wavelenghts from the antenna, not the radial system) is very good or; /archives//html/Towertalk/2001-01/msg00212.html (11,534 bytes)

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