Abstract: Lightning protection apparatus for antenna-coupled RF equipment is provided. A one quarter wavelength shorting stub bandpass filter shunts the RF equipment and a distributed capacitance, high voltage coaxial capacitor is serially coupled between the equipment and antenna. The shorting stub is tuned to one quarter wavelength of the RF equipment operating frequency. The series capacitor passes frequencies at or above the operating frequency of the RF equipment.

Abstract: An electro-optical interface unit is shown for interfacing an all-optical telephone to a conventional electrical-metallic-type telephone communications system, having conventional electrical subscriber units, switching, and supervisory systems. An overall all-optical telephone communication system, of which an all-optical telephone is a part, is envisioned. The disclosed system makes use of optical-acoustic-electrical types of transducer elements, light modulators, and optical junctions, among other novel elements.

Abstract: A master/slave opto-electrical telephone communication system utilizes a single optical fiber line to transmit out to the subordinate or slave unit from the superior or master unit two light energy carrier waves of different wavelengths, one being modulated and the other unmodulated. At the slave station, the modulated wave is demodulated and translated into sensible signals and the unmodulated wave is modulated and retransmitted to the master station where it is demodulated and translated into sensible indicia.