Sunday, June 15, 2014

80m inverted V


I built an 80m inverted V dipole and have it set up.   It is cut for a 1:1.2 or better at 3.590.   Why 3.590?   That is the frequency we are using on our digital net on sunday nights.   I was unable to hear one of the participants on my 102' doublet that is oriented E-W so in hopes of hearing him this week I put up a new antenna oriented N-S.  that will put the station on the broadside of the antenna as opposed to the ends.

So the antenna vertex is at about 44'.   The balun is a 1:1 current balun and the way it is hanging I would guess the vertex of the wire is at 42'.    Each leg was cut before tuning to 66'    .  I got his from 80m * 3 to feet = 180'.   Divide 180 by 4 to get 1/4 wavelength for each leg.  This makes each leg 60'.  Add 10% for tuning and I got 66' per leg.     I put the antenna on the tuner and wound up cutting between 1 and 2 feet off the antenna so it is roughly 65' long.

I did the math and the angle on the legs is around 105 degrees.  That falls between the ideal measurement of 90 and 120 degrees of it should be pretty good.  I have been listening and sending this weekend and it is working pretty well.  Only problem is that it has pretty narrow bandwidth.  So it is below 2:1 without a tuner only between 3.4 and 3.7mhz.


I will eave it set up for a while to examine.  It is 7-8:1 on 40m so it is really a single band antenna.  Maybe next will be to add a fan element at 40m.




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