Purchase Twinax Connectors and Cables here and Baluns here.

Twinax Tutorial

(Information compiled from internal and external sources. Wikipedia.org, etc.)

What is Twinax?

Twinax Wire
Twinax Wire - Part Number: TWX

Twinax Connector
Twinax Connector - Part Number: TAM

A type of cable similar to coax, but with two inner conductors instead of one. It is used in IBM midrange (AS/400, System/3x) communications environments.

IBM System 36 & 38
Systme38 Image
A main frame type system but with a star/bus topology and using twinaxial cable (like coax but having two cores). The System 36 and 38 are large blue and white machines with built in consoles, each of their ports support 7 devices which can be terminals or printers. The devices are daisy chained from the machines workstation controller ports, linking in and out of the terminals and printers. On sites where Type 1 or Cat 5 cable has been installed, it is usual to find 'star concentrators' or 'Loop Wiring Concentrators' (LWC), these simply carry out the daisy chaining of the terminals at the patch cabinet to enable the building to be star wired. This makes a more flexible system as the terminals do not need to be grouped in the same geographical area to be daisy chained. This means that if a person were to move to a different location in the building, they would simply plug their terminal into the nearest data outlet and re-patch the connection in the cabinet. In the past a move such as this would mean finding the nearest available line, diverting it in and out of the re-positioned terminal, and then re-addressing it.

IBM AS400
AS400 Image
This is the successor to the System 38 and its native environment is also a star/bus topology using twinaxial cable. However AS400's can also be connected over an Ethernet or Token Ring network just like a PC or a server. The advantage of this is the reliability of a main frame, with the speed and flexibility of a PC.

AS400's used to be large beige boxes that filled the air conditioned computer rooms of only a few years ago. Each rack could contain disk drives, processors or tape backup devices and required dedicated three phase supplies to power them. The modern AS400's are sleek black machines which are considerably smaller than their older counterparts, but with more processing power.



© 2011 Pacific Custom Cable, Inc.