Specifications

System Installation
RADring
Installation & Operation Manual
3-12 Module Placement Guidelines 3/11/98 12:29
Special
Considerations
Impedance of STP and UTP
The normal characteristic impedance of unshielded twisted pair (UTP)
cable, e.g. IBM Type 3 cable, is 100 ohms, and that of shielded twisted pair
(STP) cable, e.g. IBM Type 1, 2 and 6, is 150 ohms.
Token Ring Network Interface Cards
Token Ring Network Interface Cards use DB-9 female connectors and are
designed for STP (150 ohms) cables. Some NICs also provide interface to
UTP via RJ-45 connectors.
Media Filters for UTP (Token Ring only)
When using UTP cabling, media filters must be installed on the Token Ring
stations. The media filter performs the 100/150 ohm impedance conversion,
signal filtering and also adapt the DB-9 station connector to the RJ-45
connectors used on UTP.
Note
Some adapter cards already contain the on-board media filter and RJ-45
connector.
Coaxial Cable Connection (Token Ring only)
Token Ring stations can be connected by means of a single (93 ohm) RG-62
coaxial cable. At the station end a special balloon (TXC) should be used in
order to connect the adapter card (equipped with DB-9 connector) to the
BNC connector of the coaxial cable. Special versions of both coaxial
modules (TL-4/CX and TXC balloon) are available for applications with other
types of coaxial cables