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81. [Towertalk] Remote Switches (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 31 May 2002 06:17:00 -0400; VK3ZL says he has your QSL on 160, and has replied. Why is that a flaw? Shields are supposed to be permanently grounded, so why can't they be grounded at the switch? It's the way you are using antenn; /archives//html/Towertalk/2002-05/msg00850.html (8,078 bytes)
82. [Towertalk] Looking for Antenna Design (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 31 May 2002 09:10:22 -0400; Hello Kevin, If you have time, and can not model the antenna and tower, I'd suggest building a slopper out of a handbook article for 80 and 40 and trying it before trying to build something with a tr; /archives//html/Towertalk/2002-05/msg00855.html (7,481 bytes)
83. [Towertalk] Ladder Line Twist (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 1 Apr 2002 16:06:28 -0500; It depends. If the line is very long, I would twist it. If it is near something else somewhat conductive (within a few feet), I would twist it. If I didn't care if it radiated, I would not bother tw; /archives//html/Towertalk/2002-04/msg00029.html (7,095 bytes)
84. [Towertalk] The Ham Radio Business (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 2 Apr 2002 06:42:02 -0500; Nice Troll! All technical hobbies that require some work or effort have been dying, it is a cultural change. Ham radio is not unique. Neither the ARRL, Ham Radio, Wayne Green, or Samuel Morse are the; /archives//html/Towertalk/2002-04/msg00066.html (10,863 bytes)
85. [Towertalk] 40 meter beam (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 5 Apr 2002 05:40:38 -0500; I am the happy owner of a Telrex 40M yagi (the longer boom antenna), now that I have rebuilt and retuned it. In original form that antenna is what I consider over-rated junk. I spent more on repairs; /archives//html/Towertalk/2002-04/msg00171.html (8,261 bytes)
86. [Towertalk] Why capacity hats on 40-2CD (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 14 Apr 2002 20:40:12 -0400; When properly placed, capacitance hats improve bandwidth and efficiency. You can load the element with more inductance and no capacitance hat, but both bandwidth and efficiency will be reduced.73, T; /archives//html/Towertalk/2002-04/msg00506.html (7,185 bytes)
87. [Towertalk] Hook-In-Mouth (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sat, 20 Apr 2002 11:24:46 -0400; Ouch! Don't use contact cleaner on the roller, especially if you are going to transmit while rolling the roller. If you want to clean the slider, use a solvent that does not leave a residue and an i; /archives//html/Towertalk/2002-04/msg00789.html (8,402 bytes)
88. [Towertalk] antennas near water (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sat, 20 Apr 2002 11:24:45 -0400; If you look at data for ground conductivity, you will find freshwater lakes and rivers almost always have significantly lower conductivity than the surrounding soil areas. While looking out over all; /archives//html/Towertalk/2002-04/msg00790.html (7,748 bytes)
89. [Towertalk] Explain this! (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Thu, 25 Apr 2002 12:05:44 -0400; All you need is a little air moving across a very well-insulated conductor, and the normal charge gradient in air above earth can charge a conductor to many thousands of volts. I have this happen al; /archives//html/Towertalk/2002-04/msg01036.html (9,255 bytes)
90. [Towertalk] HyGain Balun (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Thu, 25 Apr 2002 12:05:43 -0400; HyGain no longer manufactures a "voltage-balun". The baluns have all been changed to current baluns, although I'm not sure the paperwork has caught up yet. Long before a balun "saturates", it will o; /archives//html/Towertalk/2002-04/msg01037.html (9,865 bytes)
91. [Towertalk] Buying nuts and bolts - Rationalized gouging (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 26 Apr 2002 07:25:13 -0400; The out-the-door cost to ship an empty "free" box, when we did a cost analysis at Ameritron in the 80's, was over $4 in direct overhead cost not including postage or shipping fees. I'm amazed we com; /archives//html/Towertalk/2002-04/msg01080.html (10,130 bytes)
92. [Towertalk] Ladder Line Twist (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 31 Mar 2002 21:31:38 -0500; There are two electrical reasons unshielded lines should be twisted. Both are caused by the fact induction and radiation fields extend outside the line. One requirement for twist is so each conducto; /archives//html/Towertalk/2002-03/msg00000.html (8,480 bytes)
93. [Towertalk] grounding an elevated vertical (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sat, 9 Mar 2002 19:22:26 -0500; Actually there was no quantitative work done at all, other than models. The only data from measurements used standard FCC slope-of-ground-conductivity measurements, and they can easily be all over t; /archives//html/Towertalk/2002-03/msg00108.html (12,491 bytes)
94. [Towertalk] grounding an elevated vertical (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 10 Mar 2002 07:52:33 -0500; ....and 120 radials are totally useless, unless the radials are about 1/2 wl long. Efficiency effectively stops increasing at about 50 radials when the radials are 1/4 wl long, and efficiency is ver; /archives//html/Towertalk/2002-03/msg00112.html (9,374 bytes)
95. [Towertalk] RF & Elec Earth Measuring (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Thu, 14 Mar 2002 05:59:16 -0500; RF (like lightning) looks for an "electrical mass" to flow into, and the return path can be via induction fields (which include "capacitance" or charge distribution effects). It is the "invisible pa; /archives//html/Towertalk/2002-03/msg00197.html (7,372 bytes)
96. [Towertalk] RF & Elec Earth Measuring (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Thu, 14 Mar 2002 05:59:16 -0500; Despite what some measurement methods might claim, you can not measure the resistance at any frequency but the operating frequency, and get an accurate result. RF resistance of a ground or of the ea; /archives//html/Towertalk/2002-03/msg00198.html (7,496 bytes)
97. [Towertalk] 1.7 db gain (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 19 Mar 2002 06:18:40 -0500; The mechanisim they describe is not true, but the effect is. One dB can mean a large increase in readability when a signal is in the presence of QRM or noise, but it has noting to do with AGC. It wo; /archives//html/Towertalk/2002-03/msg00428.html (7,938 bytes)
98. [Towertalk] EH antennas (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 22 Mar 2002 20:08:14 -0500; Hi Tim, The E-H antenna is nonsense based on the worse kind of theory. It is an offshoot of the ten-year-old CFA (that no one else outside the "inventors" has ever seen work). There are perhaps a ha; /archives//html/Towertalk/2002-03/msg00568.html (7,265 bytes)
99. [Towertalk] limitations of stacking (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 22 Mar 2002 20:08:13 -0500; Physical size has little to do with gain, and nothing directly to do with received energy. Gain comes from pattern interference, where the radiation from each antenna cancels more in some directions; /archives//html/Towertalk/2002-03/msg00569.html (8,845 bytes)
100. [Towertalk] limitations of stacking (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 25 Mar 2002 01:34:54 -0500; In my opinion it is both confusing and misleading to consider "gain" occurring from decreased radiation resistance. Pattern is what controls the directive gain. For a given applied power, and a give; /archives//html/Towertalk/2002-03/msg00616.html (9,410 bytes)

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