Quote:
Originally Posted by mallo
Hi all,
So hallosailor and sailboy21 are you saying that I don’t even need to clean the paint off? Or am I still better cleaning it off?
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Clean it off! Capacitance is determined by surface area, distance and permeability. Either a really small surface area (i.e. lug connector) or a really large distance will decrease the capacitance to zero. Capacitive coupling, at least as it relates to marine SSB installations, becomes important for fiberglass and wood boat owners trying to create a counterpoise with copper strips in the bilge. There is a coupling effect between the sea water and the copper strip through the fiberglass hull. So, a direct electrical connection is highly desirable. Also remember 'edge effect' as it relates to HF. Use large circumference materials, copper water pipe, 4 ga battery cable, and the shield of RG-8U as well as copper foil work well for this. My personal fav is the flexible 1/2" copper waterpipe. You can solder batter lugs inside the end of the tube. Makes a very sturdy HF friendly connection.
As for a corner on in the middle of a end fed short wire: avoid it if possible. You want your driven element(s) to be straight. What you get with a bend will be a strange unpredictable radiative pattern that won't be stable with changes in frequency or across bands, nulls, and probably a very high SWR that your tuner won't be able to handle. End-fed short wires are not good antennas to begin with, so you don't want to make matters worse. Perhaps you would be better going with a 17' whip like Shakespeare makes, or investigating the possible use of a shroud, or even some other antenna designs. There are many designs that are already balanced, easier to tune, portable, and that can be hoisted up when needed. I just built a nice little magnetic loop antenna that is a square with sides less than 3'. Gets better reception than any short wire and has a near perfect SWR w/o the use of a tuner.