AT 14 MC and above, compact beams giving worthwhile power gains are so easy to construct that there is little justification in considering a non-directional antenna for a permanent installation.The picture is completely different on the 3.5 mc and 7-mc bands, however; not only are even the simplest beams out of the question for most of us, but the type of operation on these bands usually requires general coverage. To retain elbow-room for higher frequency directional antennas, (and also to keep the neighborhood from looking too much like the top of a 50-family New York apartment house) it is desirable to have one antenna serve for the two lower frequency bands; This can be accomplished in a number of ways, as reviewed below, but there is one solution which eliminates drawbacks inherent in the more conventional systems.
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