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Larry W4CSC wrote:
jeannette wrote in : That's one of the reason I like the Outbacker. Besides it's made in Oz... Jeannette I've never been impressed by the Outbackers, nothing but hookup wire wrapped around a fiberglass rod with plastic taps in the continuously loaded coil whip. It's too short for a good radiation pattern below 20 meters with way too much loading and you can't put any real RF power to it which will destroy the hookup wire it's made of. "Homebrew" comes to mind under the shrink wrap exterior. Short feeler to mine, Chuukker. That and a short counterpoise. Trail an insulated wire in a hose for a "ground". Nichrome toaster wire could take more heat, huh? It also unloads your Tx automatically if the ae is too short. Some have commented they didn't like having to go out to change the taps. I'm curious how they keep the salt out of the little holes from corroding it all up. Beeswax, Billy. Lots of beeswax. Dunk the whole thing twice. A hot iron will work as a screwdriver right through it. The longest screwdriver antennas would make a MUCH more efficient HF tunable antenna for all the bands as they have continuous coverage if we could figure out how to keep from drowning their coils in seawater.... Beeswax, I say! http://www.eham.net/reviews/detail/1...90cf2ed1290b68 d5d1d http://home.earthlink.net/~jimlux/ra...crewdriver.htm http://www.dxengineering.com/Product...cID=8&DeptID=2 http://www.n2vz.com/ automatic control of screwdriver antennas....autotuner! http://www.kj7u.com/ KJ7U's screwdriver with the rubber boot looks very promising for marine use.... http://www.wb0w.com/tarheel/tarheel.htm Tarheel says theirs is for marine use. The key to all these antennas is they use a LARGE, EFFICIENT, center-loaded coil with a continuous tap that allows you, or an autotuner, to put the tuning of this antenna stump EXACTLY on your frequency, not "close enough" like an outbacker. ANY frequency as the coil is continously tuned, not banded. The idea of tuning by remote control, from the nav station for instance, is much nicer than having to go out to the outbacker in the weather on the stern to fool around with that stupid tap..... Why is that? Why not change the tap in the cabin? The wire from the autotuner is part of the radiating element array. The other end, the floating counterpoise, could go through the side and trail behind. One might think the forestay a better choise for an antenna element. The longer the whip on top of it...the better because it reduces the amount of loading coil necessary to tune it..... In radio, as with hot rods, there is no substitute for linear inches, displaced cubewise. Changing the length of the trailed element will do some of the same, could go auto with an electrolux type reel retractor and a sliding contact, or a fish tape and a roller drive contactor / retractor wheel. The sliding contacts are weak spots in all autotuners, especially if you need a kilowatt to do your toeast. (Sorry, I found it innocent, and I'm not changing it. -tk) A directional rig and polar chart can do the job a lot cheaper, and is easier to fix. Besides, you got one already, can't get rid of it, might as well learn to drive it. Turn the boat to pass your traffic. A mechanical adjustment crank and turns counter could keep a channel open if the auto tuner servo should conk out. A reference table, previously tabulated, will enable continued radio service at distant ranges and directions. Why don't GPSs provide a wordwide notices text channel? You could set a contact code to capture the text that's intended for "An english sailboat" channel. Kinda like one half of a newsgroup service. Terry K |