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181. Re: Topband: Measuring Inductor Q (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Sun, 6 Jul 2008 20:59:10 -0700 (PDT)
Jim is on the right track here. I have a slightly different approach. What I like to do is make a parallel resonant tank with the inductor under test and a high Q capacitor. (Any NP0/C0G ceramic will
/archives//html/Topband/2008-07/msg00051.html (9,971 bytes)

182. Re: Topband: Necessity of a Ground Screen under a well radialedvertical (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Wed, 06 Aug 2008 21:57:57 -0700
OTOH, I did the opposite experiment, adding 64 radials over a screen. The signal strength didn't change, but the drive impedance dropped from 70 to 36 ohms. Rick N6RK ________________________________
/archives//html/Topband/2008-08/msg00015.html (8,054 bytes)

183. Topband: CQWW 160 meter phone contest date changed (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Wed, 20 Aug 2008 09:09:34 -0700
The 2009 CQWW 160 meter phone contest has been postponed by a week to avoid conflict with the ARRL DX CW contest. Imagine the donnybrook having both contests simultaneously would have caused. (Source
/archives//html/Topband/2008-08/msg00055.html (6,627 bytes)

184. Re: Topband: Vertical question (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Fri, 5 Sep 2008 10:26:25 -0700 (PDT)
The only way to do this is to do what I do, which is to have a 450 ohm balanced to 50 ohm balanced transformer at the antenna, and operate the open wire line at fairly low SWR. Any 160 meter vertical
/archives//html/Topband/2008-09/msg00012.html (8,128 bytes)

185. Re: Topband: Vertical Question (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Fri, 5 Sep 2008 17:12:28 -0700 (PDT)
In general, a vertical or inverted L, with or without top loading, that is resonant on 160 meters with a low (<50 ohm) input impedance will also be resonant on 80 meters, but with a high (>1000 ohms)
/archives//html/Topband/2008-09/msg00014.html (9,032 bytes)

186. Re: Topband: [Topband] Inverted "L" vs." T" (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Wed, 8 Oct 2008 10:11:23 -0700 (PDT)
The higher radiation resistance and lower ground loss of the inverted L is illusory, because the additional radiation represents horizontallly polarized waves, which tend to be inefficient for commun
/archives//html/Topband/2008-10/msg00044.html (9,382 bytes)

187. Re: Topband: [Topband] Inverted "L" vs." T" (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Wed, 8 Oct 2008 13:29:22 -0700 (PDT)
Let me try this a different way. At least at my QTH, a vertical usually produces a MUCH stronger (10 to 20 dB) signal than a low (60 ft) dipole, except for locals. Therefore, any radiation produced b
/archives//html/Topband/2008-10/msg00047.html (8,842 bytes)

188. Re: Topband: " T" (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Wed, 8 Oct 2008 19:35:01 -0700 (PDT)
For a T, the sum of the vertical wire plus half the top wire should be 1/4 wl for resonance. For example, a 90 ft vertical needs an 80 ft top wire if 1/4 wave is considered 130 ft. This is a rule of
/archives//html/Topband/2008-10/msg00049.html (7,674 bytes)

189. Re: Topband: Fanning of a single tip of 1 radial (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Wed, 8 Oct 2008 19:37:00 -0700 (PDT)
Based on my experience with similar configurations, this will not work. Rick N6RK _______________________________________________ Topband mailing list Topband@contesting.com http://lists.contesting.c
/archives//html/Topband/2008-10/msg00050.html (8,106 bytes)

190. Re: Topband: Topband :"T" (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Thu, 9 Oct 2008 11:35:33 -0700 (PDT)
I have a 90 ft vertical with four 30 ft top wires that follow the guy ropes down at a 45 degree angle, and it resonates around 1.8 MHz. I have modelled various top hat configurations and the limitati
/archives//html/Topband/2008-10/msg00060.html (9,831 bytes)

191. Re: [RFI] Computer RFI on 160 (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Wed, 29 Oct 2008 13:34:43 -0700 (PDT)
Same here: I had an RFI problem with my own computer in my shack and installed a Corcom filter and it fixed the problem. It was also a homebrew whitebox computer with some junky power supply that cam
/archives//html/Topband/2008-10/msg00161.html (8,150 bytes)

192. Re: Topband: Phased Verticals (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Wed, 5 Nov 2008 14:01:02 -0800 (PST)
See the following article on a 7 element vertical array with 3/8 wave spacing: http://www.n6rk.com/7_hex_array.pdf I have only built this on 40 meters but of course it can be scaled to 160. With few
/archives//html/Topband/2008-11/msg00050.html (8,237 bytes)

193. Re: Topband: Vertical vs Inverted Vee (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Sun, 23 Nov 2008 11:44:29 -0800 (PST)
There are some issues with the ionoshere that affect verticals and dipoles differently at MF, as opposed to HF. EZNEC doesn't even claim to model those effects. I put up a full size dipole at 16 mete
/archives//html/Topband/2008-11/msg00180.html (8,302 bytes)

194. Re: Topband: Preamps (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Wed, 26 Nov 2008 16:58:24 -0800 (PST)
You might want to build the loop shown here: http://www.n6rk.com/loopantennas/pacificon.pdf You should not need a preamp with it, especially on a city lot. Rick N6RK _________________________________
/archives//html/Topband/2008-11/msg00233.html (7,015 bytes)

195. Re: Topband: DX Engineering ARAV2-1P Receive Antenna (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Thu, 27 Nov 2008 10:34:19 -0700
At my QTH, little verticals like this one receive the same as the big 90 foot transmitting vertical, in terms of signal to noise ratio. Which is to say all my verticals have made inferior receiving a
/archives//html/Topband/2008-11/msg00245.html (9,424 bytes)

196. Re: Topband: 160 meter yagi (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Thu, 27 Nov 2008 10:36:47 -0700
You would think that the station builders would put up a test dipole and compare it with a vertical before going to the trouble of building the Yagi. Rick N6RK _______________________________________
/archives//html/Topband/2008-11/msg00246.html (8,090 bytes)

197. Topband: Great condx central CA to EU for CQWW both nights (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Sun, 30 Nov 2008 18:54:43 -0700
Excellent conditions to Europe both nights of CQWW. (In Central CA, even hearing EU at all constitutes excellent conditions :-) Friday night was good early. Saturday night started out poorly, but man
/archives//html/Topband/2008-12/msg00001.html (7,861 bytes)

198. Re: Topband: DX Engineering ARAV2-1P Receive Antenna (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Wed, 03 Dec 2008 09:03:26 -0700
It has zero dB voltage gain, but a substantial power gain, because of the difference between the input and output impedance. The response is not flat across several octaves. The instructions specific
/archives//html/Topband/2008-12/msg00030.html (8,757 bytes)

199. Re: Topband: Conditions last night (score: 1)
Author: "Richard (Rick) Karlquist" <richard@karlquist.com>
Date: Mon, 08 Dec 2008 21:19:54 -0700
Correction: RW0CWA called me around 0000Z my Sunday morning. I listed him generically as a "UA9". In any event, the 9th call district in Russia is in Asia, AFAIK. On my Thursday night, before the 160
/archives//html/Topband/2008-12/msg00107.html (7,829 bytes)

200. Re: Topband: Silver solder techniques (score: 1)
Author: "Rick Karlquist" <richard@karlquist.com>
Date: Tue, 30 Dec 2008 17:16:56 -0800 (PST)
I did about 5,000 silver solder connections to build my 230 foot diameter ground screen. I used Stay-Brite solder (available at any welding supply store) and Kester pure rosin liquid flux. I used a M
/archives//html/Topband/2008-12/msg00297.html (8,633 bytes)

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