In a message dated 12/2/06 8:58:34 AM Eastern Standard Time, [EMAIL PROTECTED] writes:
> a 69-foot antenna with the feedpoint 23 feet from one side and 46 feet > from the other. From the antenna to the balun is either 55 or 111 feet of > 450-ohm line, or, 50 or 110 feet of 300-ohm line. From the balun to the rig > > is any length of 50-ohm coax. > > For 40, 20, and 10 meters, the balun is 4:1. For 15 meters, the balun is > 1:1. According to the article, no tuner is needed. I'm highly skeptical of *any* simple wire antenna that claims multiband performance without a tuner or tuner-like device. Doesn't mean the antenna's no good, just that it probably doesn't present 50+j0 on all the bands it covers. It probably comes close enough that the SWR is under 3:1, which can be matched by many rigs without a tuner and by practically any rig with a tuner - even if the tuner has limited range. Also means the coax won't have much loss. > > Since the BL2 has a switch for 4:1 or 1:1, this may be an application > without an antenna tuner. > > There is no mention of 30m, so that is an unknown. On 30 meters the antenna isn't resonant, and the feedpoint Z will be reactive. This antenna is just a version of an off-center-fed dipole. No better nor worse than any other dipole. What I like is the simplicity, light weight (the balun isn't up in the air) and the fact that if you need a long feedline, much of it can be balanced open-line, with a short piece of coax to come into the shack. It occurs to me that a double-sized version (138 feet long, feedpoint 46/92 from the ends, with feedline 110 or 222 feet long (450 ohm) or 100 or 220 feet long (300 ohm) would cover 80, 40, 30, and 20 meters, with the balun being 4:1 on 30 meters. The dimensions would almost certainly need some fussing with, but I would not be surprised if a set of lengths could be found that would do the job. If I only had the space! 73 de Jim, N2EY _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
