Audio-Data  matrices

Audio-Data  matrices


The Ro.Ma. enginery Audio /Data Matrices are used in the radiocommunication system to interface the transmitting and receiving audio/data channels to the operator consoles,  providing a capability to switch a number of input signals to a number of outputs. All the matrices are of “no blocking” type, i.e. each output has independent access to any input irrespective of the number of outputs being connected to the same input.  Modular design allows different configurations with various numbers of inputs and outputs, as required.


Main features:                                                                                                                                                       

  • Full non-blocking switch function

  • Flexible equipment configuration

  • Customer specified impedance

  • RS232, LAN 10/100 and local control

  • Options: balanced or un-balanced signal interface

Audio matrix MR-496-3, 64 x64

The MR-496-3 provides switching of 64 input lines into 64 output lines , combining in the same matrix capabilities for switching both audio and RS-232 data lines, a characteristic which allows a very versatile use of this equipment. The matrix is controlled by a microprocessor card outfitted with a programmable RS-232 serial line. The matrix is of no-blocking type, i.e capable of switching any input simultaneously to all the 64 outputs, control can be local by use of a dedicated keyboard or remote  over a RS-232/485/422 serial line.


The MR-496-3 configuration includes:

  • qty 1 CPU card for control and monitoring,  also used for the RS-232/485 serial  communication

  • qty 8 Audio/Data matrix cards, 64 inputs, 8 balanced outputs

  • qty 4 input cards for the termination of the input balanced lines

  • qty 4 optional cards for the management of the PTT signals, 2  for the 64  PTT inputs and 2 for the 64 PTT outputs

  • qty 2 power supplies, one operating and one back-up

  • qty 1 keyboard and LCD display for local control of the matrix nodes and status monitoring

  • qty 1 19” standard rack, 6 units.

The matrix is all solid state with a modular structure which allows replacement of modules during operation (with the only exception of the CPU card and front panel), each module is a 64 input x 8 input no-blocking submatrix. The matrix can be connected to 600 Ohm balanced lines and to balanced/unbalanced data lines at data rates up to 100kbit/sec.

All the interconnections are flat cables terminated with connectors, all inputs and outputs are protected against over voltage and over current conditions.  


                          - Technical characteristics

Audio inputs


Audio outputs


In/Out gain (audio)

0 dB ± 0,5 dB

3dB bandwidth ( audio)

DC to 200 KHz

No blocking loss

 2 dB max

 Input – Input isolation

> 70 dB

Output – Output isolation

> 70 dB

Switching time ( audio)

< 10 mS

Input/output impedance

600 Ohm nominal, high impedance programmable

Power handling

 20 dBm max


 1% max

Communication protocols

1) Arconia compatible 2) Elmer compatible, the two protocols are automatically recognized

Communication interface

RS 232- RS 485,  4/2 wires, dip-switch programmable

PTT (optional)

 64 Open/Ground inputs and 64 Open/Ground outputs, 28Vdc/70mA max.

Primary power

220Vac/115Vac, two power supplies, one in hot stand-by, with indication of any failure on the display.


19” standard rack, 6U , 460mm deep

Temperature range

-10°C  to +50° C



  Ro.Ma. Enginery - Via Costarica n.6 - 00040 Pomezia Roma - ITALY -                                                            Tel.: +39069112483-+390691604670 Fax: +390691141867 e-mail: