Consumer Electronics

SUBMARINE CABLES

Early submarine cables were all for telegraphy, the distortionless wider band needed for telephony could not economically be transmitted over long lengths of cable until component designers had produced long-life trouble-free units, capable of operating for many years in the depths of the oceans without fault incidence. These units, called repeaters, were designed to amplify incoming signals to offset the transmission losses incurred in the previous section of cable. It was also necessary to provide equalisation to offset the way different frequencies in the wideband information signal had been attenuated by different amounts. Such items were produced in the USA in the 1950s, and repeaters suitable for insertion in deep-sea cables ...