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References: [ +from:shristov@ptt.yu: 52 ]

Total 52 documents matching your query.

41. Re: Topband: Modeling verticals (fat, skinny, etc) on EZNEC (score: 1)
Author: Sinisa Hristov <shristov@ptt.yu>
Date: Sat, 23 Dec 2006 08:11:12 -0500
No, both EZNEC and elementary physics show that an E-W dipole sloped 45 degrees radiates exactly equal amounts of both vertical and horizontal polarization in N and S directions with zero elevation,
/archives//html/Topband/2006-12/msg00246.html (8,215 bytes)

42. Re: Topband: Unun on FT-240-61 (score: 1)
Author: Sinisa Hristov <shristov@ptt.yu>
Date: Sat, 23 Dec 2006 08:11:30 -0500
1) With FT240-61: preferably at least 8 turns of a trifilar "cable"; connect all 3 wires in series (keeping connections short and close to the core); connect 50 Ohms to the "top" and the "bottom" lea
/archives//html/Topband/2006-12/msg00247.html (7,755 bytes)

43. Re: Topband: Coax Shield vs. Ground & elevated radials (score: 1)
Author: Sinisa Hristov <shristov@ptt.yu>
Date: Fri, 29 Dec 2006 17:11:49 -0500
Unfortunately, not. As an EZNEC computation can show, even with a large number of elevated 90-degree radials, there can be a lot of common mode current, and balun requirements are much stronger than
/archives//html/Topband/2006-12/msg00330.html (7,267 bytes)

44. Re: Topband: Models and the real world (score: 1)
Author: Sinisa Hristov <shristov@ptt.yu>
Date: Sat, 30 Dec 2006 10:13:17 -0500
Agree. Depending on circumstances, it's possible to get shield current almost as strong as the antenna current. 73, Sinisa YT1NT, VE3EA _______________________________________________ Topband mailin
/archives//html/Topband/2006-12/msg00344.html (8,575 bytes)

45. Re: Topband: Models and the real world (score: 1)
Author: Sinisa Hristov <shristov@ptt.yu>
Date: Sat, 30 Dec 2006 10:15:47 -0500
I couldn't agree more with that. 73, Sinisa YT1NT, VE3EA _______________________________________________ Topband mailing list Topband@contesting.com http://lists.contesting.com/mailman/listinfo/topb
/archives//html/Topband/2006-12/msg00345.html (8,392 bytes)

46. Re: Topband: Norton preamp (score: 1)
Author: shristov@ptt.yu
Date: Sun, 21 Jan 2007 14:47:28 CET
Intercept Point values represent no real physical power. They are rather arbitrary numbers calculated from distortion measurement results. It is, therefore, perfectly possible to have such a large n
/archives//html/Topband/2007-01/msg00348.html (7,827 bytes)

47. Re: Topband: 4 square receiving array (score: 1)
Author: Sinisa Hristov <shristov@ptt.yu>
Date: Wed, 31 Jan 2007 09:39:02 -0500
Reflections and SWR can be introduced at any interface. 73, Sinisa YT1NT, VE3EA _______________________________________________ Topband mailing list Topband@contesting.com http://lists.contesting.com
/archives//html/Topband/2007-01/msg00483.html (7,495 bytes)

48. Re: Topband: Multiple Ground Systems (score: 1)
Author: Sinisa Hristov <shristov@ptt.yu>
Date: Fri, 17 Aug 2007 00:24:54 +0200
Probably the first question to be asked when considering any electrical connection is "What a current is expected to flow there and with what a purpose?". I don't know the answer in this case, but ho
/archives//html/Topband/2007-08/msg00034.html (7,105 bytes)

49. Re: Topband: How to use this tower? (score: 1)
Author: Sinisa Hristov <shristov@ptt.yu>
Date: Thu, 27 Sep 2007 23:58:49 +0200
I'd avoid half slopers and any other kind of slopers. For short and medium distance work you couldn't do better than a simple properly fed Inverted-V dipole. Make the top angle as large as possible,
/archives//html/Topband/2007-09/msg00163.html (7,838 bytes)

50. Re: Topband: One way propagation (score: 1)
Author: <shristov@ptt.yu>
Date: Mon, 12 Nov 2007 12:13:31 CET
One way propagation is impossible in a linear and isotropic medium. But the medium where HF waves propagate is neither linear nor isotropic. Therefore, one way HF propagation IS possible, although pr
/archives//html/Topband/2007-11/msg00075.html (6,949 bytes)

51. Re: Topband: A question on L's (score: 1)
Author: <shristov@ptt.yu>
Date: Fri, 16 Nov 2007 14:49:29 CET
Tom, are you saying that the bandwidth is proportional to the diameter/length ratio? Isn't it proportional to the logarithm of the ratio? 73, Sinisa YT1NT, VE3EA _____________________________________
/archives//html/Topband/2007-11/msg00137.html (6,730 bytes)

52. Re: Topband:Elevated Radial Efficiency - an inordinately long post (score: 1)
Author: <shristov@ptt.yu>
Date: Thu, 29 Nov 2007 19:06:40 CET
I'd like to ask about the feeding method used. Was the coax connected directly to the tower and radials? Was any common-mode-supressing device used? Was any attempt made to measure common-mode curren
/archives//html/Topband/2007-11/msg00260.html (7,754 bytes)


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