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In civil avation the medium-frequency range is used in locator beacon and, on occasion, for long-distance communication. The locator beacon aerials are the most frequently executed as a T-section unipoles. The horizontal part of an aerial and grounded counterpoise occupy significant territory and do not provide satisfactory power efficiency of the aerial. For elimination these lacks the symmetric short aerial (Fig. 1) was developed, in which at the same sizes of vertical parts as at T-section vibrator, the efficiency is much higher. The aerial can occupy the smaller area, than T-section vibrator, does not require a counterpoise and in number of cases increases accuracy of automatic radio compass. The aerial has received name SYPRIMA (symmetric, locator beacon) and was installed in some airports of the former USSR countries.