Hello Paolo, Mouser Electronics (www.mouser.com) has at least one of them, P/N 610-2N5109 73, Mike _______________________________________________ Topband mailing list Topband@contesting.com http://l
Hello, I'm looking for the formula to calculate the surge impedance of two wires parallel to the ground, given the diameter of the wires, the wire spacing, and height above ground. I know I've seen t
Hello, I want to thank all the friendly, helpful folks on this list who responded to my question. Not only was my original question answered, but a lot of other useful info and links were provided. 7
Hello Barry, [snip] [snip] This is a typo, and that ground should not be there. The only ground at the right (far) end of the Beverage should be on the secondary of the reflection transformer (T5a, n
We just received our new Mouser Electronics catalog today, and they have a new carbon composition resistor available that appears suitable for Beverage antenna termination resistors. They are made by
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Tue, 17 Feb 2009 17:05:57 -0800 (PST)
Dear Bill Tippett, I understand that you are the gentleman that takes care of the Topband reflector on contesting.com. I just wanted to express my deep appreciation for all your hard work since the T
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Tue, 17 Feb 2009 20:01:00 -0800 (PST)
Over the years, I've seen documentation (ARRL antenna books, US military publications) that adding chemicals around a ground rod decreases the RF ground resistance. Magnesium sulfate (Epsom salts) se
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Thu, 19 Feb 2009 15:32:12 -0800 (PST)
Hello Chuck, I was speaking of a 2-wire bi-directional 580' Beverage. I have ground rods and radials. You say that the Beverage is a special case? 73, Mike Waters W0BTU ______________________________
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Sat, 7 Mar 2009 17:51:58 -0800 (PST)
Hello, I'm putting up a second 2-wire bi-directional Beverage here, and would appreciate some opinions about what I am about to do. After much thought and planning (long story), the most logical plac
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Sun, 15 Mar 2009 11:42:45 -0700 (PDT)
Hello, I'm looking for a proven design to add 160 meters to a Heath SB-200 without disabling 80-10. I have the 1986 ARRL Handbook which shows how to add 160, but it disables all bands above 40 meters
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Mon, 22 Jun 2009 18:31:14 -0700 (PDT)
[snip] Hello Rick, Maybe I'm missing something that should be obvious, but I can't see where filter impedance matching should necessarily be a 'tall order'. There are many ways to match impedances, a
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Wed, 1 Jul 2009 15:14:43 -0700 (PDT)
[snip] WOW! Thanks for sharing this. Seeing the Tajikistan video was far more interesting than I expected. It made my day. :) 73, Mike Waters W0BTU _______________________________________________ Top
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Fri, 4 Sep 2009 14:34:15 -0700 (PDT)
Hello Toni, The impedance of the two-wire line should equal the impedance of the two wires to ground. If they do not, then you need to change the ratio of the 1:1 reflection (far end) transformer. In
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Fri, 25 Sep 2009 10:43:42 -0700 (PDT)
[snip] [snip] I read somewhere where you can prevent ice buildup on a Beverage by coating it with used motor oil before the ice storm with a paint roller. Can anyone verify this? 73 Mike ___________
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Sun, 27 Sep 2009 10:09:56 -0700 (PDT)
Hello Eddy, Well, it might sound like it. But I'm absolutely certain I read it, even though I can't find it now in a Google search. The oil made the water run off the wire like water off a duck's ba
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Thu, 1 Oct 2009 09:23:58 -0700 (PDT)
Hello Walter, Those units have a "gap" in their phase range. The range should be a full 360 degrees, but it is only about 280 degrees. If you can't get a good null, then perhaps this is the problem.
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Fri, 2 Oct 2009 18:51:49 -0700 (PDT)
Hello Joe, I appreciated your post. You said that "The "phasing" part of the W8JI design was on Tom's web site for a very long time." Sounds like it isn't there any more; do you have a copy of it, or
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Fri, 2 Oct 2009 20:11:06 -0700 (PDT)
Absolutely it is refreshing! I have the greatest respect for the Topband list and those who post here. There is nothing like it anywhere. 73, Mike Waters W0BTU ______________________________________
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Mon, 5 Oct 2009 19:50:39 -0700 (PDT)
Anyone ever try a protective anode to make their radials last? At a former QTH in NW Ohio, I had a ground-mounted vertical with 100 or so galvanized electric fence wire radials laid on the ground. F
Author: Mike Waters W0BTU <mrscience65704@yahoo.com>
Date: Thu, 8 Oct 2009 18:47:54 -0700 (PDT)
Well, if it is censorship that makes the Topband list so outstanding and enjoyable, then I'm glad it's censored. Thanks for your observations. 73 Mike _______________________________________________