Features; Applications - Black Box 3174/3274 I-Mux Series Manual

3174/3274 I-MUX

2.2 Features

Here's what you can expect from both Muxes:
• Both units are designed for use with IBM 3174
and IBM 3274 controllers (with the RPQ 9901
connection option). The Controller Side Mux
will accept up to four IBM 3174 or 3274 RPQ
9901 coaxial lines.
• Both units are fully compatible with the 3299
protocol and 3270 terminals.
• When used together, the Muxes can extend
transmission distance for IBM controllers to
3270 terminals up to about 4.7 miles (7.5 km)
(subject to polling and timing limitations).
• Both units are based on advanced VLSI
technology and offer high reliability, low power
consumption, and synchronous operation
through an independent clock. In addition to
the multiplexor functions, they provide data
signal reclocking, regeneration, and jitter
attenuation.
• When the Muxes are configured for fiberoptic
input/output, copper cable can be connected
(coax or Type 1), to provide a cold backup line.
A slide switch on the rear panel selects
fiberoptic or copper mode.
• Built-in baluns provide impedance matching
when different cable types are used (coax
[93 ohm] or Type 1, 2, 6, or 9 [150 ohm]).
• No operator intervention is required during
normal operation. The LEDs on the front panel
provide diagnostic indications for each port.
6

2.3 Applications

The Contrller Side Mux (MX330A-C) can be used
in two basic configurations. The Device Side Mux
(MX330A-D) can be used only in conjunction with
the MX330A-C.
Configuration 1:
In this configuration, the MX330A-C is used with
the MX330A-D and eight-port multiplexors. The
MX330A-C and MX330A-D are connected by
fiberoptic cable. A coaxial or twisted-pair cable
(Type 1, 2, 6, or 9) can be connected instead of
the fiberoptic cable or as a cold backup line. The
MX330A-C accepts up to four 3174 or 3274 coaxial
lines and combines them into a single multiplexed
output on fiberoptic, coax or twisted-pair cable. The
MX330A-D provides one-to-four demultiplexing.
Each line is connected to an
8-port multiplexer.
This configuration allows a maximum total distance
between controller and device of 7.5 km (see
Figure 2-3). To extend drive distance, an additional
multiplexor can be connected between the
MX330A-C and MX330A-D.
Maximum distance is subject to
controller timeout. For maximum
distance calculations, see Section
2.4.1.
NOTE