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Title: Twin lead Marconi to the rescue Post by: N6YW on July 17, 2011, 10:54:28 AM This was sent to me by my friend Jim K6SXD. It may be the only way I will get my station
on 160. http://k1ypp.home.comcast.net/~k1ypp/160MAN_D-MSword.html Title: Re: Twin lead Marconi to the rescue Post by: ve6pg on July 17, 2011, 03:19:59 PM ..this makes no sense...if you have the space for 125-130ft of wire, just run 1/4 wave on 160 (125ft) feed it with coax, and attach a ground system to the ground side...i see no advantage to this...and this is not a marconi anyway...
..tim.. ..sk. Title: Re: Twin lead Marconi to the rescue Post by: W0BTU on July 17, 2011, 05:21:13 PM Tim is correct. Just put up an inverted-L and a lay down some radials.
http://www.w0btu.com/Optimum_number_of_ground_radials_vs_radial_length.html http://www.w0btu.com/160_meters.html Title: Re: Twin lead Marconi to the rescue Post by: WD5JKO on July 17, 2011, 09:04:12 PM ..this makes no sense...if you have the space for 125-130ft of wire, just run 1/4 wave on 160 (125ft) feed it with coax, and attach a ground system to the ground side...i see no advantage to this...and this is not a marconi anyway... ..tim.. ..sk. The antenna as shown was in an old Bill Orr book. So increasing the feedpoint impedance 4X over a just a wire antenna of the same length would decrease the ground current 2X. That is a 6DB decrease in ground loss in my book, and when the Z with a single wire is low, like 10-15 ohms, doing the 4X impedance transformation gets you up near 50 ohms. I guess this is like 1/2 a folded dipole. YMMV. Oh, an antenna that is a DC short has some advantages as well over the single "floating" wire antenna. Jim WD5JKO |