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References: [ +subject:/^(?:^\s*(re|sv|fwd|fw)[\[\]\d]*[:>-]+\s*)*LF\:\s+Ground\s+loss\s*$/: 17 ]

Total 17 documents matching your query.

1. Re: LF: Ground loss (score: 1)
Author: "Rik Strobbe" <>
Date: Mon, 25 Mar 2002 16:59:32
Now I have simple LC VFO as master oscillator in my TX. I think that frequency stability is not adequate for QRSS. Is it so? I am not familar with QRSS. If I'll find XTALL for this frequency it will
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-03/msg00066.html (10,505 bytes)

2. Re: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Mon, 25 Mar 2002 22:46:35 +0000 (GMT)
Hi, Jim and Group. Will be interested to hear about any of your investigations on this subject. OK. If I'll get any sucsess in such an investigation I'll send info. Just yesterday I have understand t
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-03/msg00067.html (10,138 bytes)

3. Re: LF: Ground loss (score: 1)
Author: "James Moritz" <>
Date: Mon, 25 Mar 2002 12:29:03 +0000
Hello, lowfers! I wonder is any methods to estimate theoretically groung loss resistance of transmitting LF antenna (T-antenna with wire conterpoints mainly but others antennas also). I have good ex
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-03/msg00069.html (11,697 bytes)

4. LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Sat, 23 Mar 2002 15:19:26 +0000 (GMT)
Hello, lowfers! I wonder is any methods to estimate theoretically groung loss resistance of transmitting LF antenna (T-antenna with wire conterpoints mainly but others antennas also). I have good exp
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-03/msg00089.html (9,323 bytes)

5. RE: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Wed, 15 May 2002 19:34:52 +0000 (GMT)
Hi, Rik. TNX for the coments. I believe there is a misunderstanding, the antenna wire (Lant) remains long (several 10's meter), only the counterpoison (Lcp) is reduced to 0.2m (small ground rod). Thi
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00120.html (9,842 bytes)

6. RE: LF: Ground loss (score: 1)
Author: "Rik Strobbe" <>
Date: Wed, 15 May 2002 09:12:23
When I derive the formula I assumed wires capacitance 5 pF/meter If wire is VERY short (0.2 meters) it's not true. For such a short wire there is about 20 pF/meter. If do some corrections resistance
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00121.html (11,414 bytes)

7. RE: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Wed, 15 May 2002 11:48:34 +0000 (GMT)
Hi, Rik. too large (eg. salt water) the counterpoise won't be of much use. On the other side even for s = 0 (worst soil you can think of) R won't be endless as the counterpoise will still work. I for
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00122.html (10,319 bytes)

8. RE: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Wed, 15 May 2002 11:27:44 +0000 (GMT)
Hi, Rik. I agree about Lcp is really 0. But if I take Lcp = 0.2m (short ground rod only), Lant= 30m , C = 150pF (Xc = 7800 Ohm) and a = 0.01 then R = (Lant/Lcp)*a*Xc = 11700 Ohm. I believe that this
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00123.html (10,316 bytes)

9. RE: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Tue, 14 May 2002 21:44:34 +0000 (GMT)
Hi, Rik. I agree about Lcp is really 0. But if I take Lcp = 0.2m (short ground rod only), Lant= 30m , C = 150pF (Xc = 7800 Ohm) and a = 0.01 then R = (Lant/Lcp)*a*Xc = 11700 Ohm. I believe that this
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00126.html (10,029 bytes)

10. RE: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Tue, 14 May 2002 21:27:18 +0000 (GMT)
Hi, John Most probably you are considering a flat surface and perhaps an entirely vertical antenna? This may be all well and good for a commercial antenna, but amateur antennas like mine are not on a
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00127.html (9,695 bytes)

11. RE: LF: Ground loss (score: 1)
Author: "john sexton" <>
Date: Tue, 14 May 2002 08:53:32 -0400 (EDT)
Hi Sasha, I'm afraid this formula gives a result which is an order of magnitude less than measured here. Soil conductivity is about 0.002 Siemens/metre (chalk). From notes of one of my test configura
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00128.html (10,100 bytes)

12. RE: LF: Ground loss (score: 1)
Author: "Rik Strobbe" <>
Date: Tue, 14 May 2002 13:16:21
Hello Alex, If Lcp=0 this means that ground wire only touch to the ground in infinity small point. So R should be infinity large. If there is no conterpoint Lcp is a ground rod length. I agree about
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00129.html (10,715 bytes)

13. RE: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Tue, 14 May 2002 18:50:12 +0000 (GMT)
Hi, Rik! I believe the limitations of the formula probably are : 1.The ratio Lant/Lcp should not be too big or small. Increasing Lcp far beyond Lant won't be a great help. On the other hand, even wit
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00130.html (10,416 bytes)

14. RE: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Tue, 14 May 2002 18:49:49 +0000 (GMT)
Hi, John. Are you sure that you have written the formula correctly? Omega (2 Pi f) appears in "a" in the numerator and in "Xc" in the denominator and therefore cancels out, making the formula frequen
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00131.html (9,923 bytes)

15. RE: LF: Ground loss (score: 1)
Author: "Rik Strobbe" <>
Date: Tue, 14 May 2002 10:49:45
Hello Alex, Interesting formula. Assuming that the antenna capcity (C) is linear proportional to the antenna length (Lant) this means that Lant*Xc is a constant. Measurements have shown that the capa
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00135.html (11,671 bytes)

16. RE: LF: Ground loss (score: 1)
Author: "john sexton" <>
Date: Tue, 14 May 2002 05:47:31 -0400 (EDT)
Hi Sasha, Are you sure that you have written the formula correctly? Omega (2 Pi f) appears in "a" in the numerator and in "Xc" in the denominator and therefore cancels out, making the formula frequen
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00136.html (10,289 bytes)

17. RE: LF: Ground loss (score: 1)
Author: "Alexander S. Yurkov" <>
Date: Tue, 14 May 2002 16:17:40 +0000 (GMT)
Hi LF Group On the base of my own "generalased mirror reflection theory" I just have derive the formula for ground loss resistance: R = (lant/lcp)*a*Xc where: lant - wire length of antenna, lcp - wir
/rsgb_lf_group-archives/html/rsgb_lf_group/2002-05/msg00138.html (9,883 bytes)


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