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(N2EY) wrote in message . com...
(Brian Kelly) wrote in message . com... Cecil Moore wrote in message ... The books give all sorts of figures for "open wire line". But many of them are for the classic lines made of #14 copper spaced 4 to 6 inches with ceramic spreaders every few feet. Brown poly TV twin lead with rectangular holes punched in it is a whole 'nother ball game. 'Specially at high SWRs and when it's wet. Which may not be a consideration in NTX but is a big consideration in EPA. (a) It's only Field Day (b) If ya just gotta have "the real thing" it's out there for cheap: http://www.w7fg.com/ant.htm It can be coiled into a big helix as long as the adjacent coils are a couple of feet apart. You can run an insulated rope to the antenna feedpoint and coil the ladder-line on the rope with the coils tiewrapped a couple of feet apart. That's slick. Until the rain falls or the wind blows It rains on thousands of G5RVs every day all over the world and . . ? or somebody walks into it in the dark. .. . welcome to Field Day antenna farms . . Biggest headache, though, is switching the various lengths for different bands. No feedline switching involved here. I was thinking more along the lines of sniping one of the orange barrels which are the Pennsylvania State Flower. They're quite readily available at construction sites along the PA Turnpike and slinky-wrapping feedline around one of those should do the job. Would solve the walking-into-it problem too. The orange barrels wuz a JOKE! The big question for any FD antenna is "how many QSOs"? All the simulations and Smith charts don't count for any points - QSOs do. Exactly. So ya get a bit more loss when it rains on a G5RV, who cares?? Lemmee cite a good recent example of why too many people fuss too much with dB. here dB. there details. I was watching ops at the N3RS multiop station during the ARRL CW DX contest in March. Late in the contest the guy in the 20M seat was knocking out contacts as a respectable rate. The xcvr was an FT-1000 and the amp was a big remote-controlled ACOM. After some considerable amount of time he finally noticed that the amp had faulted and swithed itself offline when he changed bands to get on 20M. He'd been running barefoot the whole time without realizing it. The problem was sorted out, the amp was reset and off he went again this time with full power. His rate did not change by any discernable amount even though his "losses" went down by what . . 12 dB? So no, I am not gonna get my knickers in a twist over the collection of incidental losses one runs into with FD antennas and tuners. As you imply there are far more telling factors which determine the effectiveness of any station. My personal best is 629 QSOs with one 100W rig, one op, one mode, three bands and two antennas. Coax fed trapper set up as inverted V for 80/40, quarter wave groundplane elevated 5 feet with 8 sloping radials for 20. Anybody here beat that on FD with only dipoles and verticals? OK, change of topic here, I'm game. Anybody out there have well over a hundred countries confirmed on both 80 and 40 by using just a single length of end-fed wire for the antenna? 73 de Jim, N2EY |