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101. Re: Topband: "return" current - what is it? (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sun, 5 Aug 2012 11:12:37 -0400
Yuri, Kirchhoff's laws apply to ANY system when we include displacement currents. Displacement currents and Kirchhoff's laws have been around since the 1800's. As far as I know, you are the only one
/archives//html/Topband/2012-08/msg00115.html (9,956 bytes)

102. Re: Topband: "return" current - what is it? (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sun, 5 Aug 2012 12:48:06 -0400
With an infinitely long conductor, the answer is displacement currents. There is no reflected wave, and no need for a reflected wave. It's all part of Maxwell's equations. If we look at any conducto
/archives//html/Topband/2012-08/msg00123.html (9,964 bytes)

103. Re: Topband: 160 Meter Tuning Question (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Mon, 6 Aug 2012 08:37:23 -0400
Why do you want to resonate them? The shield voltage is what drives common mode onto the coax. With the radials slightly off-tune, the only problem is the shield connection voltage is a bit higher.
/archives//html/Topband/2012-08/msg00132.html (8,711 bytes)

104. Re: Topband: Fw: Re: Radials over a stone wall (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 10 Aug 2012 23:33:29 -0400
Just an out of the box thought... Anyone guess what would happen if the radials going over the wall were coax shielded ? Signed, Anonymous :-)) I wouldn't sign that either, given the fact it is impos
/archives//html/Topband/2012-08/msg00172.html (7,902 bytes)

105. Re: Topband: RX 4 SQ Phasing (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 10 Aug 2012 23:45:15 -0400
If any of us **really** had an antenna as sharp as a long Yagi, we'd need 16 or more antennas to cover useful directions. That's pretty typical behavior for a properly installed Beverage no matter w
/archives//html/Topband/2012-08/msg00174.html (8,058 bytes)

106. Re: Topband: Fw: Re: Radials over a stone wall (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sat, 11 Aug 2012 00:38:54 -0400
Good question. The radial only goes up for 4 feet and back down for 4 feet. That is exactly like adding a 4-foot shorted stub in series with the radial. All that worry about induced current in a 4-f
/archives//html/Topband/2012-08/msg00176.html (8,738 bytes)

107. Re: Topband: RX 4 SQ Phasing (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sat, 11 Aug 2012 09:44:11 -0400
If you only use ground rods or depend on earth as a counterpoise, where you place the antenna locally can matter. With a reasonably good ground, most of the losses are in the Fresnel region outside
/archives//html/Topband/2012-08/msg00180.html (11,274 bytes)

108. Re: Topband: RX 4 SQ Phasing (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sat, 11 Aug 2012 11:43:45 -0400
I don't know what "books, etc" that comes from, but even over fairly good soil a 600-foot "Beverage" models to have about 18 dB side null and a few dB F/B at 175 kHz. It isn't in "Beverage mode", bu
/archives//html/Topband/2012-08/msg00185.html (9,016 bytes)

109. Re: Topband: RX 4 SQ Phasing (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sat, 11 Aug 2012 13:24:59 -0400
There isn 't enough detail in the description to understand the model and the plots fully. A 560 foot long "beverage" on 175 kHz has about 15 dB null off the sides at 5 degrees wave angle, and a few
/archives//html/Topband/2012-08/msg00189.html (10,872 bytes)

110. Re: Topband: Image on 160M (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Mon, 13 Aug 2012 11:23:20 -0400
Wayne, Not enough information!! Any preamplifiers? Any trace of additional modulation? A mixing of BC signals will have at least a faint second modulation, **and** a mixing of BC signals or a harmoni
/archives//html/Topband/2012-08/msg00207.html (9,002 bytes)

111. Re: Topband: Image on 160M (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Tue, 14 Aug 2012 18:39:10 -0400
Roger, Broadband systems do not need to be that bad. It isn't actually a "curse". In your system it probably comes from the antenna amplifiers. Unless you have something local, a better amplifier mi
/archives//html/Topband/2012-08/msg00227.html (8,106 bytes)

112. Re: Topband: 2012/13 season opening up? (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 15 Aug 2012 08:00:40 -0400
Don't take this the wrong way, but 160 meters is open all summer and all winter long **if** people take time to operate. This is especially true in the southern USA with our shorter summer daylight p
/archives//html/Topband/2012-08/msg00233.html (8,341 bytes)

113. Re: Topband: UA9YAB - Silent Key (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 17 Aug 2012 11:42:20 -0400
That's sad to hear at such a young age. UA9YAB was a regular on 80 and 160 meters. I'm sure Alex gave many people his zone and DXCC, but most important he was a human and a fellow Ham. I hope we all
/archives//html/Topband/2012-08/msg00254.html (6,847 bytes)

114. Re: Topband: Threading radials (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 17 Aug 2012 12:20:27 -0400
I learned a lesson a long time ago here, after I used big black tie-wraps on all my cables on towers. I have white ties and ropes that are still good after 14 years, and black that fell apart after
/archives//html/Topband/2012-08/msg00257.html (8,633 bytes)

115. Topband: Ty-wraps (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 17 Aug 2012 14:13:16 -0400
I know the Home Depot ones are not. They start to break after a couple years. :-) _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
/archives//html/Topband/2012-08/msg00260.html (8,955 bytes)

116. Re: Topband: UA9YAB SK - PayPal Page (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 17 Aug 2012 17:42:23 -0400
That doesn't work for me for some reason. _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
/archives//html/Topband/2012-08/msg00269.html (8,002 bytes)

117. Re: Topband: "Missing" Buried Radials for a Monopole (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 24 Aug 2012 11:22:05 -0400
Good point, Dick. There was an AM station is Ann Arbor Michigan with the radials cut in a direction where the staion had too much field strength. The only thing that did was destabilize the array as
/archives//html/Topband/2012-08/msg00286.html (8,708 bytes)

118. Re: Topband: "Missing" Buried Radials for a Monopole (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 24 Aug 2012 12:15:10 -0400
There is no question radials radiate, and it is impossible to stop them from radiating or coupling to things around them, at least in the near field. If they didn't radiate or couple, they couldn't
/archives//html/Topband/2012-08/msg00288.html (9,523 bytes)

119. Re: Topband: "Missing" Buried Radials for a Monopole (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 24 Aug 2012 15:04:25 -0400
A vertical will radiate without any ground, and actually radiate pretty well if the common mode feedline currents can be controlled and loading losses minimized. Radiation comes from charge accelera
/archives//html/Topband/2012-08/msg00291.html (12,221 bytes)

120. Re: Topband: "Missing" Buried Radials for a Monopole (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 24 Aug 2012 16:17:22 -0400
Power is I^2, so we can assume if we divide current between enough radials each radial will not radiate much at any distance compared to the antenna. We not only have cancellation at a distance, we
/archives//html/Topband/2012-08/msg00294.html (9,516 bytes)


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