+++++++++++++++++ Date: Mon, 29 Apr 2002 18:09:31 -0500 From: Niel Wiegand To: Elecraft Mailing List Cc: kb4utz at bellsouth.net Subject: Re: [Elecraft] "Quick & Dirty" Antenna? Kirby, Since you have the antenna tuner already, I would vote for an endfed 1/2 wave wire. By being 1/2 wave long you eliminate the need for an extensive ground system. I have details of the one that I use with my K1 on my web page at http://www.io.com/~nielw/qrp2/lunchbag.htm 73, Niel - W0VLZ > > Good morning, > > Are there any suggestions as to what would be a "quick and dirty" antenna > that I could fabricate and take on the trip? Perhaps a end-fed long wire? > If so, how long, etc., etc.? > Thanks! > > ... Kirby ++++++++++++++++++++ Reply-To: From: "Ron D' Eau Claire" To: "Niel Wiegand" , "Elecraft Mailing List" Cc: Subject: RE: [Elecraft] "Quick & Dirty" Antenna? Date: Mon, 29 Apr 2002 16:49:37 -0700 > Since you have the antenna tuner already, I would vote for an end fed 1/2 > wave wire. By being 1/2 wave long you eliminate the need for an > extensive ground system. > > I have details of the one that I use with my K1 on my web page at > http://www.io.com/~nielw/qrp2/lunchbag.htm > > 73, Niel - W0VLZ > Nice package, Niel! I agree with you about 1/2 wave (or a multiple of 1/2 wavelength) being a great length to use for an end-fed wire if you have the room for it - UNLESS you get too close to exactly an electrical 1/2 wavelength long! If you do the ATU won't find a match. The impedances right at the voltage peak are too high for it. Don't throw out the idea, Kirby, if that happens to you. Just add or subtract a few feet- the impedance changes quickly near 1/2 wavelength long. Niel's plan puts the highest radiation portion (the current loop) a full 1/4 wavelength from the rig (and hopefully up in the clear) and produces the least ground losses because of the high impedance at the rig end of the wire. You do need a 1/4 wave counterpoise wire or some other r-f ground, just the same, or your rig is likely to be "hot" with r-f. Ron AC7AC K2 # 1289 +++++++++++++++++++ From: "Carter Craigie N3AO" To: "Elecraft List Members" , "Niel Wiegand" Subject: Re: [Elecraft] "Quick & Dirty" Antenna? Date: Tue, 30 Apr 2002 08:26:12 -0400 Hi Niel, I saw your message on the Elecraft reflector and then went to the "Station in a Lunch Bag" link you thoughtfully provided. I would like to build an antenna like yours. May I ask a few questions? 1. Are the two black and red wires only long enough to reach that dual binding post, say about 6 inches long? 2. If the above is correct, are you saying that you leave BOTH red and black wires connected to the binding post for 20-meter operation, but that you DISCONNECT the black wire from the binding post for 30-meter operation? 3. If you DO decide to run a ground wire, where do you suggest attaching it to the radio; and then do you just stretch it out on the ground in a straight line? 4. How long would you make that ground wire? (And I assume you'd shrink-wrap or tape the far end of the ground wire too?) Thanks in advance! 73, Carter Craigie N3AO K2 Nr. 678 K1 Nr. 159 +++++++++++++++++ To: elecraft at mailman.qth.net Date: Tue, 30 Apr 2002 09:53:27 -0500 From: n4so at juno.com Subject: [Elecraft] Antennas- Quick and Dirty QST April 2002 on Loop antennas A "One-Masted Sloop" for 40, 20, 15, 10 Meters by Rick Rogers, KI8GX-- Refers to a Sloping Loop antenna. A Balanced, Everyday Approach to All-Band Bliss by Kirk Kleinschmidt, NT0Z. I would use a shortened version of the Loop, and let the automatic tuner do it's job. The Sloping Loop in the article on page 44 requires a single high support and the tie-off points are to any convenient tree, fence or stake. No balun is required. The length of wire is not critical and the non-resonant antenna works on several bands with an antenna tuner. I use a Loop that has about 140 feet of wire and it works on 40, 20, 30 thru 15 Meter bands with a tuner. Comparison signals were made with the Loop on 15 Meters with a 15 Meter dipole. Signals were about the same. I have tested another Loop antenna for 24 Mhz and it also appeared to be broad-banded and would work on several bands with an antenna tuner. It appeared to receive equal to a 24 Mhz dipole antenna. Ken Brown-N4SO Mobile, AL EM50tk Elecraft K-1 4 ele. monoband yagi N4SO at juno.com ++++++++++++++++ To: kb4utz at bellsouth.net Cc: elecraft at mailman.qth.net Date: Tue, 30 Apr 2002 08:00:03 -0700 Subject: Re: [Elecraft] "Quick & Dirty" Antenna? From: "Mark A. Sandler" Hello Kirby: On several Boy Scout outings lately, I have used a 40 Meter dipole with excellent results. I fabricated it on site during a snow camp with insulated 24 gauge Teflon wire, fed with 47 feet of 300 Ohm twin lead. At the K2, I have a 4:1 Balun to go from balanced feed line to unbalanced K2 antenna port. It loads up nicely on many bands, and works very well on 40 Meters (resonant) and 15 meters. The dipole is 67 feet long, 33 1/2 feet each leg. I usually have it up no higher than 20 to 25 feet, and it still works well. Hope this helps and that you have a great time. I have recruited several Scouts for the Radio and Electronics Merit Badges as results of my Ham radio demonstrations. 73, Mark, K7MAS K2 #874 ++++++++++++++++ From: "df5rf" To: Subject: Re: [Elecraft] "Quick & Dirty" Antenna? Date: Wed, 1 May 2002 00:58:47 +0200 Kirby, If you go camping you might have some spare tent fibre poles left somewhere. I've bought mine as spare, half a meter of length each, 9 alltogether gives a 4.5meters "mast". It is very thin, but light-weight. It easily fits into a backpack. I replaced the inner rubber by a 1.5mm copper wire, and it can act as either a vertical for the higher bands (some radials help) or as a support for a longer wire, especially if you hike where you don't have any trees left for a dipole. I've been using a short dipole on a trip to mountains higher than 2500mtrs before and always had trouble to set it up higher than 2 meters! You can see a picture of this portable vertical on my website: http://www.qsl.net/df5rf (BTW, the picture was taken abt 200mtrs a.s.l - no real need for such a thing ..hi) Meanwhile, I have completed the antenna with camping guy ropes and pin poles, everything bought at a local camping store. 73 Gernot DF5RF +++++++++++++++++++