In what year was the first North American fiber-optic telephone system, carrying commercial telephone traffic, installed?

The first North American fiber-optic telephone system that carried commercial telephone traffic was installed in 1977. This marked a significant milestone in telecommunications technology, showcasing the capabilities of fiber optics for long-distance communication.

Prior to this, other technologies dominated the landscape, such as copper wire systems. However, by the late 1970s, studies and innovations had advanced to the point where fiber optics could effectively transmit voice signals over substantial distances with lower attenuation and less interference compared to traditional methods. The installation in 1977 demonstrated the practical application of fiber optics in everyday communications, paving the way for widespread adoption and further advancements in the field.

Understanding this timeline is crucial for recognizing the evolution of telecommunication technology and the impressive transition from analog to digital systems that has occurred since then.