If you want to cover 80m through 10m with a single wire try something in the range of 84 to 86 feet. This length is not a multiple of a half wave on any of the ham bands so it will present a reasonable impedance that can be be matched with a tuner and not surprisingly this is the W3EDP length.
If you don’t care about 80m then the suggested 26 to 29 foot wire will work great (I personally recommend 28 to 29 feet as I have found that a 26 foot wire is sometimes a bit harder to match on 40m depending on how it is deployed). Ground radial length isn’t critical, but i suggest at least 1/8 wave on the lowest frequency of operation and more is better. I normally use 5 radials made out of a 20 foot length of 5 conductor computer ribbon cable with all wires shorted together at one end and connected to a single banana plug. You then unzip the wires from the end opposite the banana plug so that you only have about 4 feet at the banana plug end that is still ‘zipped”. This makes it convenient to route the radial wires off a picnic table etc. before they splay out on the ground. When packing up I just pull all of the wires straight together and clip them together at the unzipped end with an IKEA bag clip before rolling them up. I use a 5 conductor cable as that is about my patience limit for radial deployment ;-) Cheers Michael VE3WMB / VA2NB (KX1, K1, K2) >From: Walter Underwood <[email protected] <mailto:[email protected]>> >Subject: Re: [Elecraft] Small QRP antenna question >Date: December 27, 2016 at 2:12:09 AM GMT-5 >To: Elecraft Reflector Reflector <[email protected] ><mailto:[email protected]>> >For 80 meters, try a 53 foot wire in the air. For 40 meters and up, try a wire >26 to 29 feet long. >I use a 16 foot wire laying on the ground. That length either isn’t critical, >or changes electrical length due to capacitance to RF ground at every site. Or >both. Whatever, the ATU seems to deal >with it. >I assume you have the ATU. >I have been using camping clothesline reels for the wire, but they don’t wind >up very smoothly. I just got some “midi” wire winders from SOTAbeams >(http://www.sotabeams.co.uk/midi->winders/ ><http://www.sotabeams.co.uk/midi-%3Ewinders/><http://www.sotabeams.co.uk/midi-winders/ > <http://www.sotabeams.co.uk/midi-winders/>>). The regular winders are longer >than my KX3. Haven’t used them yet. >wunder >K6WRU >Walter Underwood >CM87wj >http://observer.wunderwood.org/ <http://observer.wunderwood.org/> (my blog) ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
