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61. Topband: 2-wire Beverage (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Fri, 9 Jan 2009 09:10:12 -0800
Victor, Garry, and top-band lurkers. I had to stand back and do a little hand waving of my own. I wish I still had a blackboard on my wall. First; yes Garry, I did not say it very well. I look at a 2
/archives//html/Topband/2009-01/msg00074.html (8,365 bytes)

62. Topband: Impedance of two wires to ground? (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Wed, 14 Jan 2009 17:21:29 -0800
Here is a web link that calculates two wire Beverage transformers. Perhaps this will work for your impedance quest. I believe this to be based in the Misek book. http://www.csgnetwork.com/antennaerpc
/archives//html/Topband/2009-01/msg00135.html (7,126 bytes)

63. Topband: EZNEC and RDF (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Thu, 22 Jan 2009 09:13:40 -0800
Gm Greg and all: The simplest way I know of to get an RDF value with Eznec is to switch to the 3D view mode on the main screen and the program will do the integration for you. The average gain is the
/archives//html/Topband/2009-01/msg00227.html (7,479 bytes)

64. Topband: Odd background Noise (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Fri, 23 Jan 2009 12:52:39 -0800
Charles it is interesting you note the background noise as described. I too hear occasionally noise of similar description. The interesting thing is that it sounds a lot like the Chinese OTH radar fr
/archives//html/Topband/2009-01/msg00236.html (7,299 bytes)

65. Topband: RG-6 Coax (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Wed, 28 Jan 2009 14:50:33 -0800
Gary is spot on about so called RG-6. If you are building precision receiving arrays or even delay cables it is wise to know what you are using. I have seen some disturbing errors in phased arrays us
/archives//html/Topband/2009-01/msg00311.html (7,317 bytes)

66. Topband: RG-6 Coax (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Wed, 28 Jan 2009 15:02:20 -0800
Last message should have read 35 foot pieces of RG-6 not 5 foot! Lee K7TJR OR _______________________________________________ Topband mailing list Topband@contesting.com http://lists.contesting.com/m
/archives//html/Topband/2009-01/msg00312.html (6,612 bytes)

67. Topband: RX antenna switching (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Tue, 3 Mar 2009 09:08:42 -0800
Pete, I have had very good luck switching between radios with rotary switches on 160. Switching between different RX antennas to a single radio can be a problem due to lack of isolation. I see somewh
/archives//html/Topband/2009-03/msg00005.html (7,093 bytes)

68. Topband: How Close is Too Close? (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Mon, 30 Mar 2009 09:49:56 -0700
Mike, I agree two miles would be way too close for two high power 160 stations. In addition to your radio, you might have to also be concerned about the IMD characterisitics of any receiving array co
/archives//html/Topband/2009-03/msg00104.html (6,835 bytes)

69. Topband: How Close is Too Close? (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Mon, 30 Mar 2009 14:10:44 -0700
Mike: I lived about 1-2 miles away from the same 500kV line that Tree mentioned. I listened for 3 years on 160 and never heard a single EU station until I moved away. In the moist air that thing was
/archives//html/Topband/2009-03/msg00112.html (7,622 bytes)

70. Topband: High Desert Oregon End of season (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Tue, 31 Mar 2009 01:23:54 -0700
I guess it seems earlier every year to me when the farmer says its time to pull the RX antennas from the field. I got the word today which means by tomorrow night they will all be down. I will put up
/archives//html/Topband/2009-03/msg00122.html (8,344 bytes)

71. Topband: lift station noise (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Tue, 7 Apr 2009 19:59:30 -0700
Larry, for what its worth I have been through chasing noise from a pump as well. Many of the newer systems use what is called a VFD, variable frequency drive. Apparently there is some operating cost
/archives//html/Topband/2009-04/msg00015.html (7,419 bytes)

72. Topband: lift station noise (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Wed, 8 Apr 2009 09:12:38 -0700
Googling VFD will bring up a wealth of information related to this topic. such as: http://www.powerqualityanddrives.com/emi_rfi/ This is how we solved the Allen Bradley VFD problem here. You can surf
/archives//html/Topband/2009-04/msg00019.html (7,287 bytes)

73. Topband: Probably-dumb question re current mode chokes on RXantennas (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Mon, 18 May 2009 20:34:27 -0700
Pete, and others. There is really no difference with an amplifier or active antenna at the antenna end of a line versus passive antennas for common mode problems. Mostly the common mode currents are
/archives//html/Topband/2009-05/msg00076.html (7,533 bytes)

74. Topband: Testing Soil Conductivity (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Mon, 8 Jun 2009 08:29:05 -0700
Dont forget the good work by our top-band friend Rudy N6LF. http://www.antennasbyn6lf.com/measurement_of_soil_characteristics/ Lee K7TJR OR _______________________________________________ Topband mai
/archives//html/Topband/2009-06/msg00038.html (7,381 bytes)

75. Topband: One acre arrays (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Tue, 16 Jun 2009 16:11:23 -0700
While there is no doubt putting up 2 or 3 elements would improve your station capabilities on 160 but It makes me wonder. You have not mentioned the use of any receiving antennas at your station so I
/archives//html/Topband/2009-06/msg00059.html (7,205 bytes)

76. Topband: center-tapped common mode choke (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Tue, 7 Jul 2009 09:19:44 -0700
I have watched this thread with great interest along with the 8 element array discussion. I am curious as to how well a simple separated winding or even bifilar for that matter, transformer would wor
/archives//html/Topband/2009-07/msg00027.html (7,801 bytes)

77. Topband: Common mode chokes (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Fri, 10 Jul 2009 09:22:03 -0700
<> If I connect my receiver <> with a very short feedline (say 1m), to the antenna, I should <> not be receiving much common mode noise. Is that true? One must remember that common mode signals can a
/archives//html/Topband/2009-07/msg00039.html (8,779 bytes)

78. Topband: RECEIVING ANTENNAS (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Thu, 24 Sep 2009 23:32:46 -0700
Every design has its compromises, limitations or deficiencies. I agree with the statement as its true. In addition every location for a receiving antenna has its compromises,limitations or deficienci
/archives//html/Topband/2009-09/msg00109.html (9,554 bytes)

79. Topband: DX Engineering Receiver 4 Square using W8JI PassiveElements (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Sat, 26 Sep 2009 17:18:17 -0700
There is no doubt that the W8JI shortened verticals work well in a 160 meter array. However in the tests that I have made I would recommend a minimum of 8 radials at the base of the elements. I have
/archives//html/Topband/2009-09/msg00137.html (8,947 bytes)

80. Topband: DX Engineering Receiver 4 Square using W8JIPassiveElements (score: 1)
Author: "Lee K7TJR" <k7tjr@msn.com>
Date: Wed, 30 Sep 2009 21:51:07 -0700
On transmit a small change in phase may only change the max gain by a tenth of a dB, while a similar change in a rejection direction may lose dB's of rejection of unwanted signals.> Very well said an
/archives//html/Topband/2009-10/msg00000.html (8,920 bytes)

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