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NA7U's All-Band Doublet (80-10 Meters)
based on L. B. Cebik's 88 foot backup doublet

This antenna was modified from my NB6Zep antenna whose plots can be found here. The 88 footer is a simple concept, a dipole fed with open, ladder, or in this case, about 50ft. of TV twin lead (300 ohm). Besides simplicity, one of its virtues is that you get nice twin lobes through 20 meters. In my case, it also had the virtue of just fitting nicely between the available trees and no tails, no coils! I'm quite satisfied with the gain and patterns exhibited. The Azimuth plots shown below are arranged such that due North from my QTH is at zero degrees.

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Combined azimuth and elevation plots
80 Meters - Yep, it's only up about 1/6 of a wavelength
40 Meters - Side nulls just starting to form.
30 Meters - We're at 1/2 wavelength for this band.
20 Meters - Still nice twin lobes with side lobes just peeking out.
17 Meters - I like the pattern here better than the modified zepp, but the zepp's modeled gain is a good 2dB over this one.
15 Meters - Definitely a tighter pattern than the modified zepp.
12 Meters - Strong lobes in a quadrant pattern, very good gain. 
10 Meters - Should do nicely on 10 meters.
SWR Plot

Band K2 SWR
CALS Setting
10M 6.1 1.1
12M 6.7 1.1
15M 2.4 1.0
17M 3.4 1.1
20M 5.4 1.2 (ALT Tune)
30M >9.9 1.0
40M >9.9 1.0
80M >9.9 1.0