A Single Channel Station Carrier System for Permanent Service Applications

The 84A station carrier system was designed to have cost and performance parameters competitive with paired cable for a majority of new subscriber loops. The system design incorporates a number of unique features, not provided by previous single channel systems, which are necessary for permanent service applications. These include: bridged ringing with ring-trip during ringing, central office power for the station terminal with disconnect during off-hook, dialing, or ringing on the physical channel, and transmission suppression of ringing signals below a set threshold. This paper describes the system and discusses the electrical design and the packaging concepts. Typical performance characteristics are listed.