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121. Topband: W1WCR Beverage book (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 14 Jul 2002 12:46:37 -0400; The ground where you live is not all that good Gary. Many measurement methods published were flawed, and that results in us sometimes concluding we have better ground than we do. One method that com; /archives//html/Topband/2002-07/msg00082.html (8,571 bytes)
122. Topband: W1WCR Beverage book (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 14 Jul 2002 12:46:36 -0400; The Beverage actually responds to the voltage gradient caused by attenuation along the ground, which is just another way of saying the wave tilt. That tilt or voltage drop along the lossy earth is t; /archives//html/Topband/2002-07/msg00083.html (8,682 bytes)
123. Topband: Magnetic Slot Antenna (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 14 Jul 2002 13:38:32 -0400; I'm having problems modeling this antenna with any gain. My EZnec model with high accuracy ground and medium soil shows 17% efficiency (mostly due to ground loss) and about zero dBi gain in the best; /archives//html/Topband/2002-07/msg00084.html (7,078 bytes)
124. Topband: Beverage Transformers (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 15 Jul 2002 22:49:00 -0400; It is a mistake to think the only problem caused by not using isolated windings is noise. While that probably is a common problem, feedline common mode can also cause a loss of directivity without ad; /archives//html/Topband/2002-07/msg00097.html (9,313 bytes)
125. Topband: semi-variable Spacing and phased arrays (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 30 Jul 2002 10:39:36 -0400; Hi Ted, First, a small meander like you described would be fine. You'd never notice the difference. Second, you'd have virtually no change in directivity or S/N of the array with 200-foot spacing on; /archives//html/Topband/2002-07/msg00139.html (7,631 bytes)
126. Topband: Interesting Propagation Anomaly 5/26/02 - 0030z (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 3 Jun 2002 07:08:29 -0400; It is normal even for northern Europeans like Norway to skew south or southeast from here during summer. It is much rarer for it to happen in the winter, although it does happen. During winter, ZL's; /archives//html/Topband/2002-06/msg00006.html (8,244 bytes)
127. Topband: Re: [160m] low noise ants (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Thu, 13 Jun 2002 10:11:52 -0400; Chris and others, This question comes up frequently, and a brief summary might be useful. Magnetic loops can offer improvement in S/N if you have local noise from one primary direction. For skywave; /archives//html/Topband/2002-06/msg00022.html (8,616 bytes)
128. Topband: Beverage Frustrations (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Wed, 26 Jun 2002 20:07:53 -0400; With a direct hit almost nothing eliminates problems, but I have have very good results just using the correct components. I can have Beverage hit so hard it actually melts the wire, and the only thi; /archives//html/Topband/2002-06/msg00048.html (11,498 bytes)
129. Topband: Re: Beverage: Sloping vs. vertical drop (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 28 Jun 2002 07:02:23 -0400; Sloping the end for a modest distance probably does not hurt performance, and certainly does not help. It is mostly just a mechanical issue. I slope the ends of Beverages a bit because I use 8-foot; /archives//html/Topband/2002-06/msg00055.html (7,633 bytes)
130. Topband: Re: Beverage: Sloping vs. vertical drop (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 28 Jun 2002 19:41:17 -0400; One comment on sealing boxes. It is virtually impossible to seal a box or cable against air leakage. That is why even special gasketed transmission lines with solid copper outer conductors are kept u; /archives//html/Topband/2002-06/msg00062.html (8,882 bytes)
131. Topband: QRP DX (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 30 Jun 2002 08:27:27 -0400; In the 60's mid-west stations could work G's who were running only 5 or 10 watts, and the USA stations were running 100 watts or so by law. It took very good conditions, because we did not have packe; /archives//html/Topband/2002-06/msg00068.html (7,842 bytes)
132. Topband: Beverage Frustrations (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 30 Jun 2002 08:27:26 -0400; We have to be careful looking at very deep nulls with models. We often forget they are intentional shortcuts that use approximations designed to represent a system far too complex to calculate exact; /archives//html/Topband/2002-06/msg00069.html (8,666 bytes)
133. Topband: Power Coupling for K1B (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Fri, 3 May 2002 05:52:16 -0400; K1B's signal from their Battle Creek vertical for the last few days has almost continuously been significantly stronger than VK3ZL, who generally is the the best signal from VK and the area around V; /archives//html/Topband/2002-05/msg00018.html (7,866 bytes)
134. Topband: Power Coupling in the USA (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sat, 4 May 2002 08:34:43 -0400; I second that. I see similar effects here, and hundreds of AB tests by VK3ZL between his dipole and short vertical have showed similar results. At sunrise, it **sometimes** doesn't matter very much; /archives//html/Topband/2002-05/msg00033.html (9,385 bytes)
135. Topband: Inverted V antenna (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 5 May 2002 21:39:17 -0400; Hi Don, That's a common perception, but it isn't totally true. There isn't significantly more tilt to the horizontal component in an Inverted Vee dipole than in a conventional dipole at the same eff; /archives//html/Topband/2002-05/msg00054.html (7,336 bytes)
136. Topband: Low Dipole for RX? (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 5 May 2002 21:39:18 -0400; Low dipoles, like any receiving antenna, primarily developes S/N ratio by antenna pattern. In order to improve S/N ratio, it has to have a higher response in the direction of desired signal than und; /archives//html/Topband/2002-05/msg00055.html (7,241 bytes)
137. Topband: Horizontal vs Vertical Radiators (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 5 May 2002 21:39:19 -0400; When you mix a vertical and horizontal antenna without phase quadrature in the fields (which gives circular polarization), the result is still a single polarization. It may be skewed or tilted, but; /archives//html/Topband/2002-05/msg00056.html (7,621 bytes)
138. Topband: power coupling from C5 (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Sun, 5 May 2002 22:43:02 -0400; That's especially true when we have no idea what the pattern of our antennas are! I'm curious, any idea what the potential error is in estimates of dB coupling? How was the estimate verified Carl, o; /archives//html/Topband/2002-05/msg00057.html (6,995 bytes)
139. Topband: Power Coupling in the USA (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Mon, 6 May 2002 07:12:56 -0400; Like Bill and others, I think there is FAR too much going on to make definitive statements that at a certain latitude things "just switch" and one antenna is generally better than another. there are; /archives//html/Topband/2002-05/msg00065.html (10,752 bytes)
140. Topband: Inverted V antenna! (score: 1): Author: W8JI@contesting.com (Tom Rauch); Date: Tue, 7 May 2002 00:01:22 -0400; Hi Don and all, I may not have expressed it as well as possible, but this is worth going over if you really want to know what polarization an antenna has. All horizontal dipole style antennas gradua; /archives//html/Topband/2002-05/msg00070.html (8,707 bytes)

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