I.R.I.S. DC1100 - Manual (Page 18)

Coaxial Networks, Inc. Page 18 of 60
Coaxial Cable Specifications
The coaxial cable used to connect the IRIS DC1100 series universal broadband routers at the
Headend should be very high-quality cable. Coaxial recommends that you use a Headend-grade
coaxial cable or a quad-shield coaxial cable with a minimum of 60% + 40% braid and double foil
insulation to connect the cable modem cards to the HFC network. The center conductor must be
straight and extend 1/8 inch (3.2 mm) beyond the end of the connector, and the connector should
be securely crimped to the cable. The following cables are recommended:
• RG-6 — Standard 75 Ohm
• RG-6/U — Dual or Quad Shielded 75 Ohm
Note
The consistent use of RG-6 or RG-6/U cable is preferred to connect the cable interface to the
HFC network. If you connect an RG-6 cable to a cable interface that was previously connected
using RG-6 cable, the difference in the center connector diameter might cause intermittent
connectivity loss. If you use different types of coaxial cable, the following problems can appear:
ƒ Co-channel interference—If signals at the same frequency are carried on long, parallel runs
of coaxial cable, interference can occur between the signals. Higher quality cable helps to
prevent this with better shielding. Co-channel interference is seen as hum or patterns in
analog video channels and intermittent data loss in digital channels.
ƒ Damage to the product —Cable interface card connectors are designed for RG-6 cable and
connectors. Larger cables can damage the connectors.