Ron: Thanks for the information about the counterpoise and feedline. Would using 300 ohm twinlead work better than coax for a kooky attic dipole I constructed? With RG-6 coax and no ground, it seems to work fairly well on 40 meters. I have a couple of other antenna questions: Grounding: I am currently using the third prong of my electrical socket for that. It is connected to the house plumbing in the basement. Is this acceptable? Should I use this for dipoles and loops, as well as long wires? Reception: I have made a couple of contacts in VA and IN with folks who give me an RST of 599. In both cases, their signal was fair - around 478 at best, but drifting. I was wondering why there is such a difference. Isn't propagation usually a two-way street? Thanks. 73, Ed KB3SZZ====================
> From: r...@cobi.biz > To: doublehelix...@hotmail.com > CC: elecraft@mailman.qth.net > Subject: RE: [Elecraft] elecraft kat1 > Date: Fri, 19 Jun 2009 19:43:28 -0700 > > Hi Ed: > > I don't have a K1, but I agree with everything Don said. > > Your situation sounds a bit strange though, because I know a number of > people who have K1's who typically have not problem loading all sorts of odd > "end fed" wires. > > You are right to get rid of the coax in almost any situation like that. Coax > has huge losses at high SWRs. The ATU only ensures a match between the > antenna where it connects to the rig and the finals in your K1. It does > *nothing* to reduce the SWR on the feed line between the rig and antenna. > > A counterpoise is used to produce a low impedance at the rig. It's usually > 1/4 wavelength long. A 1/4 wave long conductor with the far end insulated > will show a low impedance at rig end. It can replace an extensive RF > grounding system, although a simple one-wire counterpoise is seldom as > effective. However, it's world's better than no counterpoise or ground at > all. Having a counterpoise or RF ground does two things: 1) It keeps > troublesome RF voltages off of the case of your K1, the key, etc. 2) It > greatly increases the efficiency of the radiator (antenna) when the antenna > is an odd multiple of 1/4 wave long or less than 1/4 wave long. > > You'll want two counterpoise wires for your setup: one 66 feet long (1/4 > wavelength on 80) and one 33 feet long (1/4 wave on 40). You can connect > both in parallel to the case or ground lug on your K1 and leave them > attached at all times. They won't interfere with each other. Indeed, you can > run the two wires alongside each other but separate them the last several > feet and be sure the ends are insulated from each other and from other > objects. > > Ron AC7AC > > > > -----Original Message----- > From: elecraft-boun...@mailman.qth.net > [mailto:elecraft-boun...@mailman.qth.net] On Behalf Of E Neubauer > Sent: Friday, June 19, 2009 6:21 PM > To: Donald Wilhelm > Cc: Elecraft Bulletin Board > Subject: Re: [Elecraft] elecraft kat1 > > > Don: > Thanks for the advice. I will definitely try those things, especially for > my attic system. Just a few moments ago, I got rid of my coax feedline > altogether and plugged my antenna wire (long wire to the backyard) directly > into the K1, via a paperclip. Wow, that made a big difference - got down to > about 1.5:1 on both 80m and 40m. > By the way, I have read things about using a _counterpoise_. Is this a sort > of substitute for a ground connection? I am interested, because we are > going to do some camping over the next couple of weeks and I am taking the > K1 along for (hopefully) some outdoor "work". > 73, Ed KB3SZZ================== > > > Date: Fri, 19 Jun 2009 20:34:09 -0400 > > From: w3...@embarqmail.com > > To: doublehelix...@hotmail.com > > CC: elecraft@mailman.qth.net > > Subject: Re: [Elecraft] elecraft kat1 > > > > Ed, > > > > One other thing - if your match varies from time to time, look for bad > > connections in your antenna system. An intermittent connection can > > allow good tuning one time and poor results at another time. > > > > 73, > > Don W3FPR > > > > E Neubauer wrote: > > > Hello: I have noticed that my k1 (with the kat1) seems to have > difficulty obtaining a low SWR with most of my antenna efforts. Most of the > time, it stays at 4:1 or higher. I have been successful at obtaining 1:1, > but it is kind of hit-or-miss and only works for one band. I live in a > townhouse, so options aren't great, but I've mostly tried long wires and > loops in the attic and yard. Still, I thought obtaining a decent match > wouldn't be so hard, especially on 40 meters. I should note that I have the > 2-band filter board for 40 & 80 meters. > > > Also, I am new to ham radio, so I am not sure whether it is safe to > operate the rig when the SWR is that high. Comments or suggestions > appreciated. > > > 73,Ed KB3SZZ > > > _________________________________________________________________ > > > Insert movie times and more without leaving HotmailR. > > > > http://windowslive.com/Tutorial/Hotmail/QuickAdd?ocid=TXT_TAGLM_WL_HM_Tutori > al_QuickAdd_062009 > > > ______________________________________________________________ > > > Elecraft mailing list > > > Home: http://mailman.qth.net/mailman/listinfo/elecraft > > > Help: http://mailman.qth.net/mmfaq.htm > > > Post: mailto:Elecraft@mailman.qth.net > > > > > > This list hosted by: http://www.qsl.net > > > Please help support this email list: http://www.qsl.net/donate.html > > > ------------------------------------------------------------------------ > > > > > > > > > No virus found in this incoming message. > > > Checked by AVG - www.avg.com > > > Version: 8.5.339 / Virus Database: 270.12.80/2187 - Release Date: > 06/19/09 06:53:00 > > > > > > > > _________________________________________________________________ > Insert movie times and more without leaving HotmailR. > http://windowslive.com/Tutorial/Hotmail/QuickAdd?ocid=TXT_TAGLM_WL_HM_Tutori > al_QuickAdd_062009 > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > _________________________________________________________________ Microsoft brings you a new way to search the web. 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