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Once upon a time ham radio was nice and easy. You just went out into your own half acre backyard, put up a pair of ninety loot telephone poles, and hung an eighty meter Zepp antenna in ihe sky. To work the old 160 meter band you fed the same sky wire as an H inverted L" against ground. On the higher frequency bands you played tuning games on ihe open wire, six hundred Ohm transmission line leading to that flat top until the fig loaded. Such olden, golden times are now only fond memories in the minds of old-timers.

Today the radio amateur h.:^ d serious problem finding enough outdoor space in which to ereci any kind of antenna, let alone an optimum one. There is, however, at least one way out of this restricted space dilemma, a way taken b\ military forces a few years back: Use an electrically small antenna! Conventional forms of such antennas, whose physical dimensions are small in comparison to the operating wavelength, are rather famous for converting more rt input power into heat than inLo good signals on the air. Antennas, unlike any other component making up a radio communications system, have stubbornly resisted efforts at miniaturization. Over the last sixty years, however, a quiet but fierce technical battle has been waged in many places in the world in an attempt to reduce the physical size of the transmitting antenna while keeping efficiency within reason. This baltle is far from won. Nevertheless, some limited progress has been made to date, as well as certain surprising gains made in terms of antenna function flexibility. As one of the weary but still enthusiastic veterans o( this technical warfare, I felt that some of the newer radiating gadgets which have come forth from the melee should be of interest and value to the radio amateur in his present hour of need. In that spirit, the aim here will be not to merely describe what some of these electromagnetic devices look like, but to include enough technical detail about them so the ham can design and experiment with these radiators himself.

Most ol the antennas discussed are forms ol radiating ri transmission lines of small electrical size. Most oi them have originated from military interest in reducing the vertical heighi and size of conventional antennas. They are still so new, however, that they exist in very small numbers as yet and only render service in military applications. As past research has disclosed thai the loading coil-only approach is the least efficient way of reactance loading short amennas, all of these newer, more exotic antennas are brought to resonance using exceedingly low loss capacitance; they make up for their high Q, narrow bandpass nature by being capable ot very rapid frequency tuning. Some, like the LPT, arc even capable of widebanded performance at good efficiency - in spite of

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