Directional couplers are becoming an increasingly important component in microwave radio-frequency circuits. By the suitable generalization of concepts used in discussing the lumped loading of a single transmission li...
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Directional couplers are becoming an increasingly important component in microwave radio-frequency circuits. By the suitable generalization of concepts used in discussing the lumped loading of a single transmission line, it is possible to discuss the interaction of the coupling elements of these more complicated circuits in a reasonably complete and elementary manner. Input impedances are analyzed in terms of equivalent tee and pi sections. The transformation of line impedances is shown to commute with similarity transformations, so that the circuit problem is equivalent to one involving independent but properly loaded transmission lines. The behavior of many aperture-coupled directional couplers may be analyzed by the use of a single conventional impedance diagram. A small-hole theory is given which predicts previously unexplained results.
While several excellent papers have been published describing the theory of operation of the annular slot radiator, certain design parameters have not been too readily available. This note gives susceptance data for p...
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The two-slot transmission line, which is the dual of a two-strip line when both lines lie in a plane, is studied experimentally when the metal sheet into which it is cut is bent through angles up to 90/spl deg/. It is...
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The two-slot transmission line, which is the dual of a two-strip line when both lines lie in a plane, is studied experimentally when the metal sheet into which it is cut is bent through angles up to 90/spl deg/. It is found that the bent two-slot line is substantially the dual of a similarly bent two-strip line including a complementary reactive junction network at the bend.
Review of the Subject.—This paper describes a new relay for automatically sectionalizing transmission lines, similar to existing relays in many respects, but equipped with “brains” so that it can determine the loca...
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The advantages of high-speed reclosing of transmission lines in 20 cycles or less are well established for voltages up to 138 kv. Up to this date little information is available however on reclosing 230 kv lines in 20...
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This paper describes a form of balun which is useful for matching a balanced circuit to an unbalanced circuit of nearly the same impedance over a wide frequency range. The bandwidth increase is obtained by the use of ...
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This paper describes a form of balun which is useful for matching a balanced circuit to an unbalanced circuit of nearly the same impedance over a wide frequency range. The bandwidth increase is obtained by the use of a quarter-wave transmission line section which is placed inside one of the balanced arms, thereby minimizing the over-all physical length. It is shown that a practical balun of this type, designed to match a 50-ohm unbalanced line to a balanced 70-ohm antenna, has a voltage standing-wave ratio of 1.4 or better over a frequency band of about 2.8 to 1. The wide bandwidth, simplicity, and reasonable physical dimensions make the balun particularly useful in connection with the adjustable-length dipole antennas which are generally used for vhf and uhf fieldstrength measurement.
High-overtone mode thickness-shear resonances in the range 2–3 GHz have been observed for the first time in Y-cut, AC-cut, and BC-cut quartz plates. High-overtone mode thickness-dilatational resonances in X-cut quart...
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