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References: [ +from:ab7echo@gmail.com: 149 ]

Total 149 documents matching your query.

41. Re: [TowerTalk] OCFD: Should I be able to do better? (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Thu, 27 May 2021 13:50:51 -0700
Joe,  you are of course correct, but I think maybe he said 576 mohms, as in 576 milliohms, although he didn't type it very clearly.  He couldn't ever have had a VSWR of 1.012 with j576 ohms. 73, Dave
/archives//html/Towertalk/2021-05/msg00169.html (9,546 bytes)

42. Re: [TowerTalk] Joining two perpendicular wires (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Mon, 12 Jul 2021 18:52:04 -0700
I don't understand these suggestions.   Steve asked about perpendicular connections, not inline, and using split bolts means that one or both of the soft copper wires is going to be under buffeting t
/archives//html/Towertalk/2021-07/msg00044.html (11,773 bytes)

43. Re: [TowerTalk] Joining two perpendicular wires (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Mon, 12 Jul 2021 20:08:53 -0700
There is a bend over a sharp edge, and by definition it is at least 45 degrees for one or more of the wires. I've used them ... but only for connections not under tension. 73, Dave   AB7E I don't und
/archives//html/Towertalk/2021-07/msg00046.html (13,817 bytes)

44. Re: [TowerTalk] Joining two perpendicular wires (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Tue, 13 Jul 2021 12:30:51 -0700
It's the tin in solder that weathers from moisture.  The water leaches out the tin and leaves a soft, porous matrix that has very little strength.  The white powder you often see is the lead oxidizin
/archives//html/Towertalk/2021-07/msg00065.html (11,321 bytes)

45. Re: [TowerTalk] Dipole center connector (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Thu, 22 Jul 2021 12:05:11 -0700
I've made my own almost exactly like that as well except I don't use zip ties for the coax ... I've never had a zip tie, even the outdoor rated ones, hold up for even a full year under the UV that I
/archives//html/Towertalk/2021-07/msg00091.html (10,225 bytes)

46. Re: [TowerTalk] remote reading multimeter (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Mon, 26 Jul 2021 11:41:36 -0700
This is probably more hassle than you want to bother with, but there are some other ideas here as well. https://hackaday.com/2015/02/01/give-your-multimeter-a-wireless-remote-display/ 73, Dave   AB7E
/archives//html/Towertalk/2021-07/msg00132.html (8,550 bytes)

47. Re: [TowerTalk] How critical is the 120 degree ... (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Tue, 27 Jul 2021 11:00:52 -0700
The first question seem like a rather simple vector analysis task to me.  Generate a simple model for the manufacturer's recommendations for included angles, distance from tower, and guy wire tension
/archives//html/Towertalk/2021-07/msg00151.html (10,565 bytes)

48. Re: [TowerTalk] Beverage Antenna Mounted 12' Above Gorund (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Tue, 31 Aug 2021 19:58:10 -0700
Since actual RF ground could be almost anywhere (and could be definitive or graded) depending upon your soil, practically speaking the difference between 12' and 10' is a meaningless distinction. The
/archives//html/Towertalk/2021-08/msg00153.html (8,670 bytes)

49. Re: [TowerTalk] Beverage Antenna Mounted 12' Above Gorund (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Tue, 31 Aug 2021 23:55:38 -0700
Hi, Jim. Well, by "RF ground" I meant the conductive (actually semiconductive) zone of the earth as seen by the incoming RF relative to the wire.  "Ground" is the same term used in modeling programs
/archives//html/Towertalk/2021-09/msg00001.html (11,446 bytes)

50. Re: [TowerTalk] Beverage Antenna Mounted 12' Above Gorund (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Fri, 3 Sep 2021 11:50:46 -0700
I could certainly believe that to be the case.  If your ground conditions are such that the effective reference is not near the surface, lower is probably better since a Beverage high off the ground
/archives//html/Towertalk/2021-09/msg00026.html (9,833 bytes)

51. Re: [TowerTalk] Beverage Antenna Mounted 12' Above Gorund (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Fri, 3 Sep 2021 12:21:25 -0700
I run the BOG to keep the wire BELOW the deer.  ;) And with the monsoon rains we've had here this summer I'd have to run the wire about five feet high to stay above the four foot high wiry invasive A
/archives//html/Towertalk/2021-09/msg00030.html (12,073 bytes)

52. Re: [TowerTalk] TH-7 (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Fri, 3 Sep 2021 14:15:54 -0700
There are two different effects here in that comparison.  One is the stacking gain for the four stack, but the other is the difference in takeoff angle for an antenna on 20m at a height of 140' versu
/archives//html/Towertalk/2021-09/msg00035.html (9,224 bytes)

53. Re: [TowerTalk] Earth Ground: How good is good enough (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Thu, 9 Sep 2021 16:43:52 -0700
"Please don't get your cart before my horse." So somebody misunderstands your query and you react like that?? Your post specifically asked about RF grounds.  You say the "why" is not relevant, but it
/archives//html/Towertalk/2021-09/msg00101.html (13,415 bytes)

54. Re: [TowerTalk] Fwd: Earth Ground: How good is good enough (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Fri, 10 Sep 2021 19:42:02 -0700
As NR1DX has rather pointedly made clear, none of us know what kind project he is actually working on or why he wants the information, and we certainly don't know that it is for a tower ground.  Sinc
/archives//html/Towertalk/2021-09/msg00124.html (13,682 bytes)

55. Re: [TowerTalk] Unique Shunt-Feed Tower question (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Wed, 15 Sep 2021 22:30:27 -0700
I've never tried this but I have often wondered the same thing.  A wire running down the outside of the tower basically just forms a shorted parallel wire transmission line along with a portion of th
/archives//html/Towertalk/2021-09/msg00139.html (8,233 bytes)

56. Re: [TowerTalk] Unique Shunt Feed (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Thu, 16 Sep 2021 12:20:34 -0700
I don't see the link, but I assume this is it: http://www.vias.org/radioanteng/radio_antenna_engineering_02_03_04.html Another way of thinking of a shunt fed tower is that it is a folded monopole (ha
/archives//html/Towertalk/2021-09/msg00146.html (9,419 bytes)

57. [TowerTalk] T-Network Calculator Spreadsheet (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Wed, 22 Sep 2021 19:12:41 -0700
There are several online T-Network and L-Network calculators out there, as well as various standalone applications that do the same thing.  My problem with most of them, though, is that every time I
/archives//html/Towertalk/2021-09/msg00186.html (10,859 bytes)

58. Re: [TowerTalk] T-Network Calculator Spreadsheet (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Wed, 22 Sep 2021 21:58:10 -0700
You didn't actually look at the spreadsheet, did you ... Dave   AB7E 73 Rick N6RK There are several online T-Network and L-Network calculators out there, as well as various standalone applications th
/archives//html/Towertalk/2021-09/msg00190.html (8,338 bytes)

59. Re: [TowerTalk] Weird lightning hit (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Fri, 1 Oct 2021 13:04:59 -0700
All lightning is weird and unpredictable.  There are countless stories of lightning hitting something on the ground while missing a nearby pole, tower, building, or tree. 73, Dave   AB7E Recently the
/archives//html/Towertalk/2021-10/msg00004.html (9,017 bytes)

60. Re: [TowerTalk] Weird lightning hit (score: 1)
Author: David Gilbert <ab7echo@gmail.com>
Date: Fri, 1 Oct 2021 16:45:21 -0700
I'm pretty certain that how well the tower is installed has next to nothing to do with whether or not lightning strikes it. What happens if and when the tower does get hit could be a different story,
/archives//html/Towertalk/2021-10/msg00007.html (10,921 bytes)


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