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81. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 4 Jul 2012 09:39:38 -0400
Undesired power levels are **generally** worse from a higher frequency element to a lower frequency element, rather than the other way around. The wider the spread the greater the difference. My 15M
/archives//html/CQ-Contest/2012-07/msg00028.html (10,139 bytes)

82. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 4 Jul 2012 11:30:03 -0400
Sometimes things get useful when the information is wider. <<snip>> I disagree with that, Jukka. Traditional filters neither route things to a ground nor dissipate a significant portion of unwanted
/archives//html/CQ-Contest/2012-07/msg00029.html (13,968 bytes)

83. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 4 Jul 2012 11:31:02 -0400
No, not if you want to know the true amount of available power. :-) See my long post. _______________________________________________ CQ-Contest mailing list CQ-Contest@contesting.com http://lists.c
/archives//html/CQ-Contest/2012-07/msg00030.html (9,208 bytes)

84. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 4 Jul 2012 14:21:12 -0400
It could be much more than that, actually. Maximum power transfer would occur when the optimum impedance on 15 meters for the 20 meter element is presented. The simple cheap test would be installing
/archives//html/CQ-Contest/2012-07/msg00036.html (12,762 bytes)

85. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Thu, 5 Jul 2012 07:49:48 -0400
It's pretty simple to do. I have a 8 position switch box in my radio room that has stubs on ports. This is the same box that selects antenna trunks to different areas. I use steering diodes to activ
/archives//html/CQ-Contest/2012-07/msg00039.html (11,814 bytes)

86. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 6 Jul 2012 14:31:28 -0400
I was considering band splitters to allow single feeders to be used on multiple bands to save cable, not necessarily for feeding one antenna. I would split bands at both ends. The only worry I had,
/archives//html/CQ-Contest/2012-07/msg00050.html (10,278 bytes)

87. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sat, 7 Jul 2012 10:06:44 -0400
Here is the problem, although appearently it is difficult to get across. :-) Filters do not dissipate out-of-band power, they reflect it. Stress on the filter will vary with filter placement on the
/archives//html/CQ-Contest/2012-07/msg00053.html (11,540 bytes)

88. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sat, 7 Jul 2012 19:19:22 -0400
Hi Guy, The reason why I find this interesting really centers around two things: 1.) making things work as well as possible for the investment appeals to me 2.) it's interesting to learn how stubs a
/archives//html/CQ-Contest/2012-07/msg00058.html (9,588 bytes)

89. Re: [CQ-Contest] Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Mon, 9 Jul 2012 08:09:30 -0400
Keith, I added a SPICE model of two low pass 3.6 MHz filters to my webpage. You'll see the stress on parts there for a 100 volt peak source through a 50 ohm resistor, which is about like a 50 watt t
/archives//html/CQ-Contest/2012-07/msg00076.html (11,833 bytes)

90. Re: [CQ-Contest] IARU Contest Rulrs. (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Tue, 10 Jul 2012 07:45:31 -0400
6.4. The use of non-amateur radio means of communications (e.g. telephone or the Internet) for the purpose of soliciting a contact (or contacts) during the contest period is inconsistent with the spi
/archives//html/CQ-Contest/2012-07/msg00089.html (8,570 bytes)

91. Re: [CQ-Contest] Fw: Bandpass filter (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Tue, 10 Jul 2012 11:22:48 -0400
Snubber micas are good capacitors, generally they work out better than conventional micas in RF systems, but they are not really characterized for high power RF applications. Over the years the data
/archives//html/CQ-Contest/2012-07/msg00095.html (9,311 bytes)

92. Re: [CQ-Contest] 500 Watt Amp or 1500 Watt Amp (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Tue, 17 Jul 2012 08:17:20 -0400
Dave, Thanks for the great examples of how things really work!! None of the silly nonsense that 1 dB = 100 QSO's or other junk science. The result of this, is anyone will see, is a little bit of gain
/archives//html/CQ-Contest/2012-07/msg00169.html (10,793 bytes)

93. Re: [CQ-Contest] Coax Stubs Again. (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 18 Jul 2012 16:21:33 -0400
The stub operates at near infinite SWR, so it does not need to be a 50 ohm stub. You'll do OK on the pass frequency because the higher impedance offsets the extra cable loss, but the notch won't be
/archives//html/CQ-Contest/2012-07/msg00199.html (7,243 bytes)

94. Re: [CQ-Contest] Stubs (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Thu, 19 Jul 2012 22:36:47 -0400
The correct combination of series lumped component and 1/4 wave 15M stub could make an open on 15 and short on 40. RG6 it would take a ~500 pF cap in series with the center conductor on a 15 meter s
/archives//html/CQ-Contest/2012-07/msg00218.html (8,670 bytes)

95. Re: [CQ-Contest] Stubs - 40 & 15 meters (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Fri, 20 Jul 2012 17:32:23 -0400
Thinking about that logically, it appears it would still pass 40 meters to me. The reactance of a 30 degree shorted stub is the same but opposite sign as a 60 degree open stub. The result would be a
/archives//html/CQ-Contest/2012-07/msg00228.html (8,483 bytes)

96. Re: [CQ-Contest] Stubs - 40 & 15 meters (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sat, 21 Jul 2012 07:46:47 -0400
Real stubs in real systems can have over 15 dB variation in attenuation, depending on electrical spacing from the antenna, and a lesser extent spacing from the amplifier or radio (which usually is d
/archives//html/CQ-Contest/2012-07/msg00233.html (9,429 bytes)

97. Re: [CQ-Contest] CQ contest submission deadline getting (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 25 Jul 2012 14:01:39 -0400
I sure agree with that. We have deadlines at the front to get ready, and weekend restrictions. With new close deadlines added to the end, it just extends the weekend even more. For people who have n
/archives//html/CQ-Contest/2012-07/msg00303.html (8,420 bytes)

98. Re: [CQ-Contest] Log submission time (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Wed, 25 Jul 2012 20:42:31 -0400
My bet is on an increase in non-submitted logs, not that those logs matter all that much. _______________________________________________ CQ-Contest mailing list CQ-Contest@contesting.com http://lis
/archives//html/CQ-Contest/2012-07/msg00320.html (7,386 bytes)

99. Re: [CQ-Contest] Log submission time (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Thu, 26 Jul 2012 11:40:41 -0400
Sarcasm does not come off well in written text. I was being sarcastic. My guess or assumption (which is all most of this is, lacking full statistics) is those who are accustomed to creating files an
/archives//html/CQ-Contest/2012-07/msg00335.html (9,382 bytes)

100. Re: [CQ-Contest] Life of Coax (score: 1)
Author: "Tom W8JI" <w8ji@w8ji.com>
Date: Sun, 29 Jul 2012 11:15:36 -0400
I would measure it, which is easy to do accurately with a dummy load, radio, and a movable power meter. I have 20-30 year old cables that are well within new cable loss specs. The primary cause of e
/archives//html/CQ-Contest/2012-07/msg00366.html (8,408 bytes)


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