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41. Re: Topband: Yaesu Key clicks (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Mon, 29 Nov 2004 08:23:50 -0600
Some folks with megastations like yours tend to lose sight of how the majority of hams have to live. A month ago, I sat at my mountaintop station in CA and had a bunch of 160 Q's on a Saturday night
/archives//html/Topband/2004-11/msg00256.html (9,538 bytes)

42. Re: Topband: ARRL-160 viewed frm EU (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sun, 05 Dec 2004 15:33:25 -0600
The stations you hear (and who hear you) are those with decent antenna farms. Many of us in the contest have poor antennas and lots of receive noise. I and two other of my friends here in Chicago (K9
/archives//html/Topband/2004-12/msg00083.html (8,826 bytes)

43. Re: Fw: Topband: ARRL-160 viewed frm EU (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sun, 05 Dec 2004 15:39:08 -0600
Yes. There was a lot of QRM (lots of stations in the contest), many of us have lots of noise (same problem that some of the DXpeditions are having now), and no land to construct receive antennas (Bev
/archives//html/Topband/2004-12/msg00084.html (7,908 bytes)

44. Re: Topband: The Stew Perry TopBand DX Challenge IX (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 15 Dec 2004 11:50:11 -0600
This is a contest I haven't worked before and want to this year. There is an obvious error on the link, but it isn't obvious (to this new participant) what the correction should be. The link lists th
/archives//html/Topband/2004-12/msg00209.html (8,200 bytes)

45. Re: Topband: Logging the Stew Perry (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 17 Dec 2004 09:49:20 -0600
WriteLog has a module for Stew Perry. Jim Brown K9YC _______________________________________________ Topband mailing list Topband@contesting.com http://lists.contesting.com/mailman/listinfo/topband
/archives//html/Topband/2004-12/msg00236.html (6,965 bytes)

46. RE: Topband: Re: Coax capacitor losses (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sat, 18 Dec 2004 10:30:10 -0600
On Fri, 17 Dec 2004 20:40:09 -0800, Richard (Rick) Karlquist (N6RK) wrote: But you had better use a Smith chart for at least part of the design work. Based on its length and the frequency at which it
/archives//html/Topband/2004-12/msg00250.html (8,423 bytes)

47. Re: Topband: buried radial problems. (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 22 Dec 2004 10:32:38 -0600
Probably because resistance to ground of such a limited ground system is fairly high, which adds to the low radiation resistance of your antenna to get you closer to 50 ohms. In other words, you may
/archives//html/Topband/2004-12/msg00280.html (8,895 bytes)

48. Re: Topband: New Antenna (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Sun, 26 Dec 2004 18:39:50 -0600
I like your #1 and #2 ideas the best, and I've heard some pretty decent signals with this sort of arrangement. But accept it as a given that all of the ideas you've mentioned require a decent ground
/archives//html/Topband/2004-12/msg00307.html (7,858 bytes)

49. Re: Topband: -77 ferrites (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Mon, 27 Dec 2004 13:08:56 -0600
Thanks for the pointer, Rudy. The Fair-Rite Products catalog, available free as a pdf on Fair-Rite's website, is also VERY useful and tutorial. Jim Brown K9YC ________________________________________
/archives//html/Topband/2004-12/msg00323.html (7,228 bytes)

50. RE: Topband: FT-240-77 Toroid Impedance R + jX Components (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Mon, 27 Dec 2004 17:49:55 -0600
it I'll take a stab at it, Chuck. I've also measured a bunch of ferrite chokes, both single turn and multiple turns. It is VERY important to understand that these are not transformers, they are choke
/archives//html/Topband/2004-12/msg00328.html (9,182 bytes)

51. RE: Topband: FT-240-77 Toroid Impedance R + jX Components (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Tue, 28 Dec 2004 11:28:46 -0600
1) Consider how the X component affects your particular installation. Would capacitive reactance cause a resonance at the frequency you are transmitting (or at another frequency that could be nearby
/archives//html/Topband/2004-12/msg00334.html (10,360 bytes)

52. Re: Topband: FT-240-77 Toroid Impedance R + jX Components (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 29 Dec 2004 13:19:16 -0600
I would revise that to say that chokes are most effective and most easily used if there is a low shunting impedance across the load. Yes, I would love to have a low shunt Z across the load, but I'm n
/archives//html/Topband/2004-12/msg00341.html (9,253 bytes)

53. [TowerTalk] White Paper On Power and Grounding (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 29 Dec 2004 20:44:11 -0600
Here's a link to a paper I just finished on Power and Grounding for Audio and Audio/Video systems. While some of the material is specific to the needs of those systems, much of it is generic and appl
/archives//html/Topband/2004-12/msg00344.html (7,607 bytes)

54. Re: Topband: Re: Increasing bandwidth 160m L (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Thu, 30 Dec 2004 13:21:21 -0600
What is your aversion to networks? I find that a good L-section tuner will cover all or most of the band with minimal retuning. I use one of the TenTec KW tuners, and have replaced all the fixed capa
/archives//html/Topband/2004-12/msg00353.html (7,955 bytes)

55. Re: Topband: Electric Fence Noise (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 07 Jan 2005 09:36:02 -0600
Neat idea, John! Here's another. The ARRL AC Power Interference Book by Marv Loftness, KB7KK, observes that a source of arcing is much easier to DF on its VHF components. He says most power system EM
/archives//html/Topband/2005-01/msg00090.html (7,538 bytes)

56. Topband: Key-clicks FT1000MK-V field ? -- SEND IT BACK! (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Wed, 19 Jan 2005 07:35:32 -0600
Being "nice" and "civil" clearly hasn't worked. There are two parts to this problem -- the guy who buys a radio with clicks and the company who sells it. These radios are clearly defective. Send them
/archives//html/Topband/2005-01/msg00231.html (9,771 bytes)

57. Re: Topband: T-antenna vs Inverted L (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Tue, 25 Jan 2005 15:55:54 -0600
This is pretty close to what I am doing, and pretty close to the example in Kraus "Antennas". It's the first example in the "Antennas for Special Applications" chapter (21-2.1b in a recent paperback
/archives//html/Topband/2005-01/msg00288.html (7,814 bytes)

58. Re: Topband: Contest weekend (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Thu, 03 Feb 2005 00:11:14 -0600
You (and lots of other guys working HF, especially 160) need to realize that those of us living in cities have noise levels that are 10-20 dB higher than those of us living in the country. Moreover,
/archives//html/Topband/2005-02/msg00054.html (8,178 bytes)

59. Re: Topband: 160M 9V1 & DX Contest at W3LPL (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Tue, 22 Feb 2005 00:41:23 -0600
Yeah, get out the violins. CU2M actually heard me calling him Saturday night with 100 watts to a bastard long wire from a Chicago city lot but couldn't copy my call. I was thrilled, and at the same t
/archives//html/Topband/2005-02/msg00212.html (7,920 bytes)

60. Re: Topband: Need help in winning a Preamp Wager (score: 1)
Author: "Jim Brown" <jim@audiosystemsgroup.com>
Date: Fri, 25 Feb 2005 08:39:03 -0600
loss at 1.8 MHz. The only reason I can think of that remote mounting would be better is if the input of the preamp is at an impedance significantly different from that of the cable that comes into th
/archives//html/Topband/2005-02/msg00232.html (8,280 bytes)


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