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References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*Topband\:\s+Ground\s+conductivity\,\s+permittivity\s+measurement\s*$/: 16 ]

Total 16 documents matching your query.

1. Topband: Ground conductivity, permittivity measurement (score: 1)
Author: cris blak <cyo3fff@yahoo.com>
Date: Tue, 2 Oct 2012 03:31:10 -0700 (PDT)
Hello all,   I like to share my experiments and hear from your similar experiments regarding ground conductivity and permittivity measurements.   As we all know (should know), those two parameters ar
/archives//html/Topband/2012-10/msg00030.html (10,275 bytes)

2. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Tue, 2 Oct 2012 09:40:55 -0400
As we all know (should know), those two parameters are esential to evaluate the ground under our antennas, especially for verticals. The ideea to measure the ground concuctivity and permittivity rise
/archives//html/Topband/2012-10/msg00038.html (10,080 bytes)

3. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: Jim Brown <jim@audiosystemsgroup.com>
Date: Tue, 02 Oct 2012 10:22:59 -0700
Excellent work, Cristi. A suggestion for this last part of the analysis. Rather than look at the vertical angle where the radiation peaks, look at the field strength at some chosen low angle, like 10
/archives//html/Topband/2012-10/msg00050.html (8,508 bytes)

4. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Paul Christensen" <w9ac@arrl.net>
Date: Tue, 2 Oct 2012 13:35:37 -0400
Excellent work, Cristi. A suggestion for this last part of the analysis. Rather than look at the vertical angle where the radiation peaks, look at the field strength at some chosen low angle, like 10
/archives//html/Topband/2012-10/msg00053.html (8,006 bytes)

5. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: Dan Zimmerman N3OX <n3ox@n3ox.net>
Date: Tue, 2 Oct 2012 14:17:51 -0400
I don't know about further out where you'd have to proof an AM station but I just ran some models and there's kind of a weird relationship between vertical electric field strength at 1 wavelength ou
/archives//html/Topband/2012-10/msg00061.html (9,153 bytes)

6. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Tue, 2 Oct 2012 14:30:18 -0400
I don't know about further out where you'd have to proof an AM station but I just ran some models and there's kind of a weird relationship between vertical electric field strength at 1 wavelength out
/archives//html/Topband/2012-10/msg00062.html (9,237 bytes)

7. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Tue, 2 Oct 2012 13:58:04 -0500
Conclusion: The less ground conductivity the higher is the antenna elevation radiation angle. This is a negative impact for DX! Cris, Tom, Paul et al This belief is common when looking at the far-fie
/archives//html/Topband/2012-10/msg00069.html (11,561 bytes)

8. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: Guy Olinger K2AV <olinger@bellsouth.net>
Date: Tue, 2 Oct 2012 15:07:02 -0400
When you do problems like this with modeling, be careful. While the wire moments are specifically calculated segment by segment, what gets calculated around ground is not literal calculation like the
/archives//html/Topband/2012-10/msg00071.html (12,106 bytes)

9. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: Guy Olinger K2AV <olinger@bellsouth.net>
Date: Tue, 2 Oct 2012 15:13:27 -0400
Hi Richard, On your referenced fields graph you caption "Measured vs. Calculated" intensity, but the traces are not differentiated. Which traces on the graph are measured and which are calculated? 73
/archives//html/Topband/2012-10/msg00073.html (12,266 bytes)

10. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Tue, 2 Oct 2012 14:33:58 -0500
On your referenced fields graph you caption "Measured vs. Calculated" intensity, but the traces are not differentiated. Which traces on the graph are measured and which are calculated? ______________
/archives//html/Topband/2012-10/msg00075.html (9,141 bytes)

11. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Paul Christensen" <w9ac@arrl.net>
Date: Tue, 2 Oct 2012 15:39:38 -0400
To Rich's point, I created a buried field in 4NEC2 using the radial geometry wizard and a vertical wire radiator 40m tall, all wires being of #12. The radial field consists of 64, 0.5 wavelength radi
/archives//html/Topband/2012-10/msg00077.html (13,273 bytes)

12. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: Jim Brown <jim@audiosystemsgroup.com>
Date: Tue, 02 Oct 2012 13:01:54 -0700
See Rudy's work, on his website. 73, Jim K9YC _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
/archives//html/Topband/2012-10/msg00079.html (9,236 bytes)

13. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: cris blak <cyo3fff@yahoo.com>
Date: Wed, 3 Oct 2012 06:59:02 -0700 (PDT)
Hello Tom,   My comments are on your message (below). I measured the impedance from 1 to 180MHz continuously with miniVNA. The presented values (27 to 5mS/m) are for 1833kHz so, are not useless. I do
/archives//html/Topband/2012-10/msg00139.html (14,712 bytes)

14. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Richard Fry" <rfry@adams.net>
Date: Wed, 3 Oct 2012 09:03:00 -0500
From Terman (as Richard Fry mentioned): http://i62.photobucket.com/albums/h85/rfry-100/TermanFig55.jpg First hop distance on E layer reflection for given angles is: 20 degrees = 300miles, 30 degrees
/archives//html/Topband/2012-10/msg00140.html (10,707 bytes)

15. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 3 Oct 2012 10:20:34 -0400
Cristi, Thank you for the thoughtful answer. If I was of a mind to verify the use of probes, I would look at the attenuation slope of sample signal from a distance source across the area being measur
/archives//html/Topband/2012-10/msg00143.html (11,774 bytes)

16. Re: Topband: Ground conductivity, permittivity measurement (score: 1)
Author: Jim Brown <jim@audiosystemsgroup.com>
Date: Wed, 03 Oct 2012 08:56:43 -0700
On 10/3/2012 7:20 AM, Tom W8JI wrote: I would agree with your idea about multiple points making it meaningful if you also moved the probes deep below ground, to a depth where the field diminished to
/archives//html/Topband/2012-10/msg00153.html (10,988 bytes)


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