Dipoles and a bit about loops

 I use both a halfway dipole cut for 15 meters and a dipole cut for the CW end of 40 meters for 15 meters. 

The dipole gives about 7 or 8 dBi gain broadside.The 40 meter dipole gives maybe  a bit more gain but in four narrow directions. If I did not need an antenna for 40 meters I would just as soon have two 15 meter dipoles at right angles.  I did something similar this year on 10 meters. I ended up with three dipoles, one NE/SW, one E/W and one N/S on a three position remote switch.  Sometimes switching gave me one or two S-unit increase with the right antenna. Peak gain was from EZNEC was almost 8 dBi and the minimum gain at any point was never more than 3 dB down from that with one of the three antennas and that was only at precisely two compass points. I have had large Yagis on ten metersand switching between these three dipoles felt like instantly swinging a Yagi! A dipole is a really good antenna if high and broadside to the desired direction. It is the nulls on any antenna that really hurt.The null off the end of a good dipole can be two or more S-units. Some longer wires have more nulls. I think nulls are bad and want to avoid having them if possible.


one note about loops. A Quad loop is never going to be more than two in phase dipoles spaced at 1/4 wavelength with their ends bent down to touch. Two in phase dipoles stacked at 0.6 wavelengths might give almost 5 dB gain over one dipole but with stacked dipoles at 1/4 wave the gain drops to about 1 dB. The Quad loop is definitely no more than that and I think usually a bit less. Other loops are going to be even worse than that.  

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