- 1. Re: Topband: 160M_AC_BUZZ (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Sat, 11 Aug 2007 15:54:29 -0500
- Yep, arcing is the magic word. I finally built an arc detector (QST April 2006, modified) to find problems like this. The last one I tracked down turned out to be located 3 miles from my house. I was
- /archives//html/Topband/2007-08/msg00015.html (8,096 bytes)
- 2. Re: Topband: A Big Mess! (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Fri, 17 Aug 2007 17:03:18 -0500
- Be careful with that WD40. I used that stuff to clean some barrel connectors used in my receiving antennas. The residual WD40, left in the connector, floated some black conductive junk out of the con
- /archives//html/Topband/2007-08/msg00044.html (7,819 bytes)
- 3. Re: Topband: CAPACITOR VALUE FOR INVERTED L ANTENNA (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Fri, 31 Aug 2007 01:04:25 -0500
- Assuming the end of the top part of the L is also at 50 ft, and that you have about 16 radials of about 1/4 wavelength, and average ground, for resonance at 1.83 MHz you need about 400 pf. The resist
- /archives//html/Topband/2007-08/msg00141.html (8,209 bytes)
- 4. Re: Topband: Ground resistance (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Sun, 09 Sep 2007 20:30:41 -0500
- Here is a good article on the same subject and the conclusion is exactly the opposite. http://www.kkn.net/dayton2004/ Look at all the articles by N6LF on grounding. Jerry, K4SAV _____________________
- /archives//html/Topband/2007-09/msg00050.html (7,524 bytes)
- 5. Re: Topband: Ground resistance (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Mon, 10 Sep 2007 11:17:46 -0500
- -- Here is N6LF's home page. He has a huge collection really good articles. The best collection of articles on ground measurements, characteristics, and radial systems I have ever seen. This is reall
- /archives//html/Topband/2007-09/msg00055.html (7,309 bytes)
- 6. Re: Topband: High voltage and coupling from a vertical to adjacentcoax (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Sun, 07 Oct 2007 19:45:03 -0500
- That sounds like a very short vertical for top band. It should resonate somewhere around 4.1 MHz. The resistive part of the feedpoint impedance should be somewhere around 3 ohms on 160, which means i
- /archives//html/Topband/2007-10/msg00014.html (8,726 bytes)
- 7. Re: Topband: Need Help IDing Noise (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Sat, 20 Oct 2007 10:19:14 -0500
- Looking at the waveforms, the 160 meter recording has very strong 2.5 KHz and 120 Hz components. The 40 meter recording has very strong 1.75 KHz and 120 Hz components. It appears as something arcing
- /archives//html/Topband/2007-10/msg00098.html (8,322 bytes)
- 8. Re: Topband: Silver Plated Conductor (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Tue, 20 Nov 2007 18:54:56 -0600
- Before you consider silver plating a coil, here is something you should know. At 2 MHz the RF skin depth in silver is 0.00178 inches. You need about three skin depths of plating, that's about 0.0053
- /archives//html/Topband/2007-11/msg00163.html (7,287 bytes)
- 9. Re: Topband: Resistance wire in Beverages????? (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Thu, 22 Nov 2007 19:56:54 -0600
- I put this on EZNEC to look at what all that resistance does, compared to using normal Beverage wire. I used a 160 meter Beverage that was only 1 meter off the ground. On 160 meters, using the 15 ohm
- /archives//html/Topband/2007-11/msg00188.html (8,463 bytes)
- 10. Re: Topband: de n7dd (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Mon, 03 Dec 2007 09:15:01 -0600
- I can understand the confusion on the multipliers for the ARRL 160 contest. I can't really answer the question, but I can add to the confusion. The rules say: 5.2. Multipliers: ARRL/RAC Sections (max
- /archives//html/Topband/2007-12/msg00020.html (9,123 bytes)
- 11. Re: Topband: big K9AY-loop + MFJ 10126 (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Sun, 23 Dec 2007 10:44:11 -0600
- The best size for a K9AY (or EWE, pendant, flag, etc) is a compromise between gain and lobe shape. As you go down in frequency the shape of the lobes of these antennas gets better but the gain drops
- /archives//html/Topband/2007-12/msg00163.html (11,308 bytes)
- 12. Re: Topband: noise analysis w/ soundcard (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Sun, 30 Dec 2007 22:47:04 -0600
- If you are only looking to detect the presence of 60 Hz or related harmonics present within noise, a PSK31 waterfall will do the job. It will also detect other frequencies present within the noise. T
- /archives//html/Topband/2007-12/msg00233.html (7,665 bytes)
- 13. Re: Topband: Ant Analyzer Assistance request -- funky readings (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Thu, 24 Jan 2008 16:23:45 -0600
- The same reading on 3.6 MHz with the loop open or closed really threw me for a moment until I realized that this is an off-center-fed open loop. So about 30 feet high should get you into the low teen
- /archives//html/Topband/2008-01/msg00178.html (8,554 bytes)
- 14. Re: Topband: radial depth (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Tue, 29 Jan 2008 18:37:25 -0600
- While that may be true as a general guideline, it needs to be tempered a bit depending on the frequency and quality of the soil. On 160 meters with average soil the depth of penetration is about 20 f
- /archives//html/Topband/2008-01/msg00199.html (8,297 bytes)
- 15. Re: Topband: Half Slopers (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Mon, 04 Feb 2008 17:39:40 -0600
- -- I like Tom's name for this antenna best, "half slopper". You can think of the sloping element as a matching network for feeding the tower. The exact configuration of the tower determines how well
- /archives//html/Topband/2008-02/msg00018.html (10,946 bytes)
- 16. Re: Topband: Half Slopers (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Mon, 04 Feb 2008 20:12:36 -0600
- I called it a half sloper because that is what you did. It was obvious from your post what antenna you were talking about, so no confusion there, but to be correct, I should say this about the names.
- /archives//html/Topband/2008-02/msg00020.html (7,887 bytes)
- 17. Re: Topband: Half Slopers (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Mon, 04 Feb 2008 22:17:25 -0600
- I have to modify some of my quick answers. K4SAV: I answered this question a little too quickly and without details. The Yagis don't contribute any significant radiation to the total if they are symm
- /archives//html/Topband/2008-02/msg00021.html (8,444 bytes)
- 18. Re: Topband: Direct fed tower (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Mon, 11 Feb 2008 10:40:58 -0600
- Radiation wise it doesn't matter whether you feed the tower or radials. However, since the coax will be close to the tower, to minimize the potential across the coax outer cover, it is best to connec
- /archives//html/Topband/2008-02/msg00064.html (9,513 bytes)
- 19. Re: Topband: Snow plus vertical (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Thu, 28 Feb 2008 09:21:20 -0600
- The extra length at the bottom, between the feedpoint and the radials, will look like part of the antenna. It will move the resonant frequency slightly and the feedpoint impedance a little. It's like
- /archives//html/Topband/2008-02/msg00136.html (8,360 bytes)
- 20. Re: Topband: End Fed Twin Lead Marconi Antenna (score: 1)
- Author: K4SAV <RadioIR@charter.net>
- Date: Tue, 04 Mar 2008 12:03:32 -0600
- EZNEC says the antenna you described, over a good radial system, should be resonant at about 2.0 MHz with a feedpoint impedance of about 163 ohms (with some variations depending on wire used). The f
- /archives//html/Topband/2008-03/msg00012.html (8,183 bytes)
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