1240 CNS Multiplexer

1240 CNS Multiplexer

Proven solution for Radio Status or System Management Monitoring.

1240 CNS Multiplexer, Key Features, IP & non IP

The Ethernet IP interfaces of the 1240 CNS Multiplexer support Radar Asterix, VoIP ED137 and System Monitoring. Proven ED137B & C VoIP operation, for up to 16 Ground/Air Radios with a separate IP network for Radio Status, SNMP or System Management Monitoring. The same CNS Multiplexer simultaneously supports up to 8 legacy Air/Ground Radios, (4 wire Voice + E&M signalling, with or without phantom earth), permitting easier transition from existing 25kHz to 8.33kHz Radios. For ATIS requirements, mostly 4 wire Voice + E&M, the 1240 CNS Multiplexer supports both current equipment and new VoIP systems.

For Data requirements there are X.21/RS422/RS485 & RS232 (V.24) interfaces, primarily used on Navigational Aids and some Radars.

Dual power feeds to the 1240 CNS Multiplexer are provided to minimise a single point of failure.

The 1240 CNS Multiplexer has an 18Vdc to 72Vdc input range, accommodating site locations having either 24V or 48V DC battery systems (positive or negative earth).

There is a generous 30dB optical light budget, maintained over the lifetime of the 1240 CNS Multiplexer, achieved by the built in compensation correcting sustaining the Laser's output level. 60Km distances should easily be achievable. Extended versions offer 120Km (over single mode Fibre).

1240 CNS Multiplexer

Provides transport of both Ethernet and non-Ethernet interfaces

Ethernet support for Radar Asterix, VoIP ED137 and system monitoring

Proven ED137B & C VoIP operation for multiple ground/air radios

Simultaneous transmission of multiple legacy ground/air radios (4 Wire E&M)

Dual power feeds to minimise single point of failure: 86-264Vac and/or 18-72Vdc

Serial support for nav aids and radar (X.21/RS422/RS485 & RS232)

1240 Multiplexer scheme

The FT-1240CNS fibre optic multiplexer provides transport for a variety of voice and data interfaces.

Dual 10/100Mbps Ethernet implemented as two independent links

High speed serial n x 64kbps to 2.048Mbps - X.21, RS422 or RS485

8 x RS232 / V.24 interfaces - Async to 38.4kbps and Sync to 64kbps - Full Flow control DSR/DTR, CTS/RTS & DCD

8 x 4 wire Audio 3400Hz + E&M signalling. phantom earth signalling and -50Vdc

8 x Volt Free Relays

Dual power feeds 86-264Vac & 18-72Vdc

Multi and singlemode fibre options


Item Description
User ports
8 RS232, Async to 38K4, Sync to 64K
4/8 E&M Voice
2 X.21/6 RS422
0/8 Relay I/O
Trunk port
Guaranteed 30dB power budget
LED Indicators
Optical Rx
Full Duplex Operation
Optical Rx Power Level
Master (M) or Slave (S)
Temp: 0C to +60C Operating
Humidity: 90%RH to 50C, 80% RH non condensing 30 to 50C
Physical 435mm x 195mm x 44mm
Power Consumption 20W Max (12W typ)

A key strength of the 1240 CNS Multiplexer is its versatility to network/integrate all Aviation Manufacturers of:


Navigational Aids


Equipment/Systems to a (Digital) Control Tower

Combination of Ethernet and Non-IP interfaces provide a cost effective solution for transitioning to new CNS IP based Systems.
The 1240 CNS Multiplexer assists the Safety Case with its proven operational track record.

Do you have any questions?

For further information please contact FTI.
You can ask us a question using the form or please call us on
+44 (0) 24 7641 7070.

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