Quabbin Wire & Cable Co., Inc. has introduced a new family of double-shielded Type 735A coaxial cables designed for efficient DS-3 digital signaling. The explosive growth of Internet connections, complex wide-area-networks, cellular phone systems, and exponentially increasing data-streams through Telco infrastructure has created huge demand for these cables.
These new coaxial cables can be used as a system with Quabbin's previously developed DS-1 (T-1) multipair cables. Both now provide an integrated copper cabling solution for handling time-division multiplexing (TDM) of digital information at large LAN installations, cellular phone systems, or Telco central offices. Where the previously developed DS-1 cables handle up to 24 digital channels (1.54 MHz bandwidth), this new design transmits up to 672 channels with a bandwidth of 44.7 MHz!
Applications include data premises where multiple DS-1 circuits are employed in service entrance facilities and riser installations, cellular phone systems, or in central office environments interconnecting DS-3/DS-1 routers, bridges, or switches. The cable is most often terminated using readily available BNC type connectors.
These new coaxial designs use a 26 AWG solid silver-plated copper conductor with an efficient high-density foamed or cellular insulation. This provides a high velocity of propagation, combined with low signal distortion. A double shield consisting of 100 percent coverage aluminum/polyester tape and 90 percent coverage braid provides both signal return path and EMI isolation. A flame-retardant high density PVC jacket gives the cable excellent mechanical protection and an NEC/CEC CMR fire resistant listing. Electrically, P/N 2735 has a mutual capacitance of 17.5 pF per foot combined with 75 percent velocity of propagation. The characteristic impedance is 75 Ohms with 30 dB minimum return loss through 95 MHz. The attenuation at 50 MHz is only 3.47 dB per 100 foot.