Subject: Re[2]: too high antenna?
To: Bill Fisher - W4AN <w4an@contesting.com>
???? Well, guess I have to disagree w/ you.? Talking 10 m., I was comparing
???? 170' with 90'.? 90' is already relatively high in terms of wl.,
???? therefore one won't see the difference from a REAL high antenna as
???? often, which most often is at the lowest angles.? Also, I was speaking
???? in reference to 1) a stack - where if you have big beams you get 5db
???? over a small, single beam and 2) frequently? the "off" or multiplier
???? antenna needs to break a pile-up.
????
???? I agree with you about 20 meters, having used Duffy's stuff, and
???? having had antennas at all different heights.? Remember that in your
???? example of 210' on 20 it's only 105' on 10 - I think that that may be
???? a point where diminishing returns begin to come into play - Anecdotal
???? evidence aside (K6EBB worked a G on 10 w/3el at 180', nobody out here
???? worked one) - in single op contesting particularly rate is a key
???? factor, and the REAL high antenna won't give you that very often
???? (still talking 10 here - REAL high must be defined in terms of wl, NOT
???? in terms of common hardware - 200' is not real high on 40)
????
???? I remember 2 specific instances on 20:? listening to a UA9, stack of
???? 5el/46'boom at 65/125 and a 205ba @80'- bottom beam, barely readable,
???? 205 - s5-7, top beam - s9, and stack well over 9.? The other was a WPX
???? with a single 205ba at 160' - at 10z sunday morning, I could hear all
???? the west eu talking to each other, not working any US.? It was like I
???? was on their continent.
????
???? Bottom line:? very low angle is often far superior, BUT is there a
???? point where the lower angle doesn't propagate any better??
????
???? On 10, where high (w/l) antennas are easy (100-120'), one needs to get
???? as much gain as possible to differentiate from the crowd.?? That would
???? be as big (boom) a stack as practical- and 3 or 4 high would be a way
???? to go.? Note how dominating w9re has been on 15 the last few years
???? since he went to his 4 high, both gain AND low angle.
????
???? As far as gain goes, I would expect my 42' yagi (a dl1bu) to have
???? 2.5-3db gain over the 20'(w2pv) one.? That is the same as a doubling
???? of power.? While the g3 may not notice a big difference, the t77 will
???? pick you out of a pile a HECK of a lot quicker.
????
???? btw, you'll love a full size 3 el 40.? Might want to keep it on the
???? low side?? 100-120'?? Mine was frequently too high in the mid-opening,
???? although a killer at 0800z and before sunset (2nd lobe?).? it was at
???? 170'.
????
???? Greg
Bill Fisher, W4AN (EX KM9P)
http://www.contesting.com
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