Abstract: A high frequency antenna that is particularly suitable for marine environts. The high frequency antenna has a metallic base flange, a metallic spring assembly for permitting flexibility and shock resistance and a metallic sleeve all maintained at ground potential so that the antenna is immune to being shorted out such as by salt water and preferably comprised of stainless steel. The radiating element of the antenna is formed on a fiberglass rod and is comprised of a flat, ribbon-like conductor or a plurality of wires approximating a ribbon like conductor. The radiating conductor is wound around the fiberglass rod such that the wound or wrapped areas have a width that is substantially equal to the non-wrapped areas on the rod to permit the ribbon-like conductor to radiate from both sides in order to achieve a low profile antenna.

Abstract: A wideband VHF antenna operable simultaneously on multiple frequencies hag an instantaneous bandwidth greater than one octave and having a total length less than one-quarter wavelength at the lowest operating frequency. A wideband impedance transformer is connected to the antenna total radiating structure at the feed point. The radiating structure comprises a conductor secured to a dielectric whip. The conductor is comprised of two sections of length L1 connected by a short length of electrical connector to form a large loop. The radiating structure further comprises a second electrical conductor of length L2 connected by another short length of electrical connector so as to form a small loop. The length L2 conductor is disposed in the neutral plane between the two conductor sections of length L1.

Abstract: A noise rejection circuit for a communications receiver in which the input o the receiver is continually sampled by a sweeping heterodyne oscillator to develop a difference frequency noise signal which represents the input noise over a wide frequency band. The receiver input is also processed by a conventional heterodyne oscillator to develop an output at an intermediate frequency that is comprised of the desired signal plus the noise component. Further processing of both the swept heterodyne oscillator and the normal heterodyne oscillator outputs in a differential combiner serves to remove the noise from the desired data signal.