Manual
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Table of Contents
Introduction .................................................................................................................................................. 3
1. Radio Modem MR400 ............................................................................................................................. 4
Radio Part MR400 ......................................................................................................................................... 5
Modem Part ............................................................................................................................................ 5
3. MR 400 Connectors ...................................................................................................................................... 6
Antenna .................................................................................................................................................... 6
Serial Interface ....................................................................................................................................... 6
RS232, RS422 and RS485 Connectors..................................................................................... 6
Distinguishing Data Modules by Colour .......................................................................................... 6
Ethernet .................................................................................................................................................... 7
Analog and Binary Inputs and Outputs .......................................................................................... 7
Labelling ........................................................................................................................................... 7
Parameters ..................................................................................................................................... 7
Supply Connector ....................................................................................................................................... 8
Information LED .................................................................................................................................. 8
Service Connector ................................................................................................................................ 9
4. Table of Technical Parameters .............................................................................................................. 10
5. Dimensional Diagram .............................................................................................................................. 11
6. Labelling Radio Modems ....................................................................................................................... 12
7. Conditions for MR400 Operation ............................................................................................................ 13
Radio modem instalation and maintenence ................................................................................................ 13
Conditions of Liability for Defects and Instructions for Safe Operation of Equipment ............................ 14
Declaration of Conformity ......................................................................................................................... 15
Limitations of Use ...................................................................................................................................... 16
List of Figures
1. Radio modem MR400 .............................................................................................................................. 3
3.1. Service connector connections .......................................................................................................... 9
3.2. View of radio modem – description of connectors, model with DSUB (Canon)
connectors and with terminals .................................................................................................................... 10
5.1. Mechanical dimensions of MR400 .................................................................................................. 12
6.1. Serial codes of products ....................................................................................................................... 13
List of Tables
3.1. Table of data cable connections ........................................................................................................ 7
3.2. Table for distinguishing LEDs for RxD and TxD by colour ....................................................... 7
3.3. Table of Ethernet to cable connector connections ....................................................................... 8
3.4. Table of digital and analog input and output parameters ........................................................... 8
3.5. Table of service connector connections .......................................................................................... 9
4.1. Table of technical parameters ............................................................................................................. 13
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Introduction
This operator manual serves as the primary document for familiarising users with the parameters of the radio modem, its
properties, modifications and with the parameters of interfaces. In order to master all the functions of the radio modem
and the MORSE system you should refer to other documents.
Figure 1. Radio modem MR400 (MR300, MR160)
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1. Radio Modem MR400 (MR300, MR160)
MR 400, MR300 and MR160 are conceptually new radio modems designed for transmitting data in the VHF and UHF
bands. The radio modem uses 4-state FSK modulation providing for a maximum signalling rate of 21.68 kbit/s. The
radio modem is of modular design with one to four standard RS232 ports (an RS422 or RS485 port can be used in
place of two of them) available to the user. The configuration can be extended by an Ethernet interface and also by a
module with analog and digital inputs/outputs, which is normally provides two analog inputs and outputs and two
digital inputs and outputs. The radio data transceiver module can be configured to an arbitrary frequency of the
transmitter and receiver within the 3.2 MHz frequency range in a 12.5 kHz channel raster. The receiving and
transmitting frequencies are mutually independent and are derived from the frequencies of four Phase-Locked Loops
programmed by the transceiver microprocessor. Channel settings are stored in the transceiver EEPROM memory and
the FLASH memory module of the modem whose central processor controls the operation of the transceiver
microprocessor. The RF output power of the radiomodem transmitter’s high frequency signal is software-configurable
in sixteen steps from 0.1 to 5 W. The software configuration of MR400 is backward compatible with that of the MR25
radio modem. A description of software control and configuration of the MR25 is available in publications describing
MORSE Firmware.
Important
ATTENTION! The radio modem is equipment which can only be operated in the Czech Republic on the basis
of Permission to operate transmitting radio stations issued by the Department of Frequency Spectrum
Management at the Czech Telecommunication Office.
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2. Description of Functions
Radio Part MR400
The architecture of MR400 (MR300, MR160) radio modems resolves most of the requirements placed on a top
quality user friendly radio modem with a very short switching time between receiving and transmitting.
Frequency synthesis enables software selection of an arbitrary channel from the given frequency range. The
operation of the radio part is controlled and diagnosed by the microcontroller. The receiving part of the radio
modem is a double-conversion superheterodyne. The overall selectivity is divided between both intermediate
frequency levels. The first filter carries out the necessary channel pre-selection which ensures the linear function
of the following second mixer and intermediate frequency amplifier. The second filter has the attenuation
characteristic necessary for channel selection in the used channel spacing of 25 kHz (12.5 kHz). Logic circuits,
switching the radio part between modes of receiving and transmitting, have high noise immunity and switch
respective blocks sequentially. This minimises transient parasite states and optimises bandwidth during
switching. Switching to the transmitting mode is blocked when the frequency synthesiser is out of lock or the
internal temperature exceeds a hardware set limit or the supply voltage falls below the value ensuring proper
functioning of the device.
Modem Part
The control microcomputer has 4 MB of FLASH memory and 16 MB of RAM memory available. The battery
backup-ed real-time clock, detector of supply voltage failure and watch-dog circuits belong amongst the other
circuits of this block. If there is a supply voltage failure the fact is recorded into memory with the respective
timestamp thanks to the charge stored in electrolytic capacitors. The user therefore has information available
about the time and duration of possible faults caused by power failures. It is possible to connect equipment with
signalling rates up to 115.2 kbit/s to the modem via the RS232 data interface. RS232 interface converters are
protected against overvoltage with TRANSIL elements. A lithium battery is used for backing up in the modem
part.
Important warning – a risk of explosion!
The lithium battery must not be replaced by an incorrect type. When in doubt, leave the replacement to
the manufacturer.
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3. MR 400 Connectors
Antenna
The antenna connector is of the N type, female, impedance 50 Ohm. The antenna cable must be fitted with an
appropriate mate. We recommend using the RG213 50 Ohm cable. The H1000 cable should be used when the
length of the antenna feeder exceeds 25 m.
Important
CAUTION. The radio modem should be powered only when the antenna (or artifical load) is
connected. Otherwise it could lead to damage to the radio part of the modem.
Serial Interface
According to the configuration of the radio modem it is possible to use a terminal block or DSUB 9 (Canon)
connectors for connecting data cables via the serial interface. See Chapter 6 Labelling radio modems.
RS232, RS422 and RS485 Connectors
Table 3.1. Table of data cable connections
Terminals RS232 DSUB9F RS422 Canon RS422
1 CTS 8 TxD- 7
2 RTS 7 TxD+ 3
3 RxD 2 RxD- 8
4 TxD 3 RxD+ 2
5 GND 5 GND 5
When RS485 interface is needed, the RS422 pin layout applies. It is necessary to shortcut TxD- to RxD- and
Txd+ to RxD+ to obtain the respective Data-, Data+ RS485 signals.
Distinguishing Data Modules by Colour
For RS232 RxD is the output from the radio modem (approx. -8V when inactive) and TxD is the input to the
radio modem (according to the RS 232 standard). Hardware versions of the interface can be distinguished
according to the colours of LED diodes next to the connector.
Table 3.2. Table for distinguishing LEDs for RxD and TxD by colour
Type of interface Colour (RxD / TxD)
RS232 red / green
RS232 optically coupled orange / green
RS422/485 optically coupled orange / yellow
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Ethernet
Connector RJ-45 for Ethernet 10BaseT and 100BaseT corresponds to the EIA TIA T568B standard. Informative
LED diodes indicate: Tx – output from CU Rx – input to CU 100 – if lit the 100BaseT LINK network is
indicated – indicates correctly connected F.D. link – indicates full duplex operation. A “straight” cable is needed
for connecting to the Ethernet network via the hub (repeater) or switch-hub (router). A “crossed” cable is mostly
used when just two devices are connected “back-to-back”. E.g. MR400 to MC100, MR400 to a PC, etc. The
following table contains connector connections and colours of conductors. For the crossed cable the order of
conductors on one side is the same as for the direct cable.
Table 3.3. Table of Ethernet to cable connector connections.
PIN Signal Direct cable Crossed cable
1 TX+ white - orange white - green
2 TX- orange green
3 RX+ white - green white - orange
4 — blue blue
5 — white - blue white - blue
6 Rx- green orange
7 — white - brown white - brown
8 — brown brown
Analog and Binary Inputs and Outputs
Labelling
Individual terminals of terminal blocks are labelled:
Connector A OUT - analog outputs
Connector A IN - analog inputs
Connector D OUT - digital outputs
Connector D IN - digital inputs From left to right: 1. input / output + 1. input / output - 0. input /
output + 0. input / output
- Terminal UP – From left to right: + - if a voltage of +2.4 to 15 V is brought to this terminal the radio modem
activates, firmware carries out the pre-programmed step according to settings in configuration (wake up from
sleep mode). Sleep mode is resolved by individual SW settings GND.
Parameters
Table 3.4. Table of digital and analog input and output parameters
2 × optically coupled digital output Bipolar solid state switch
(max. 30 V/500 mA)
Passive
2 × optically coupled digital input 2.4 – 15 V log. 1 0 – 2.4 V log. 0 Passive
2 × optically coupled analog output 0 – 20 mA Rz max = 250 Ohm Passive
2 × optically coupled analog input 0 – 20 mA/4 – 20 mA SW switchable (input
impedance 60 Ohm)
Passive
Analog inputs 0 and 1 have connected terminals ”-” (minus), which are galvanically isolated from the modem
GND. Analog outputs 0 and 1 have connected terminals ”-” (minus), which are galvanically isolated from the
modem GND.
Supply Connector
Terminals of this connector are labelled in the standard manner. Only DC voltage in the range from 10.8 to 15.6
V can be connected to the device. Voltages outside this range may damage the radio modem. Terminal PI
(power indicator): if the radio modem is fed from the MS2000 power supply information from this source is
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passed to this terminal about the method of supply; level TTL0 – 230 V AC supply, TTL1 – battery supply. If
the radio modem is supplied in another manner the method of supply is deduced according to the voltage (the
value from which the supply is considered as supply from a battery can be set in SW).
Information LED
Information LED diodes next to the supply connector:
RF Tx — radio modem transmits
RS SYNC — radio modem received message header which was destined for it
Three following LED (signal strength):
ON ON ON — RSS <85 (stronger signal)
OFF ON ON — RSS 85 to 95
OFF OFF ON — RSS 95 to 115
OFF OFF OFF — RSS > 115
POWER ON — radio modem is correctly supplied
Service Connector
The service connector is used for temporary connections of the service cable during local adjustment of radio
modem parameters. Upon attaching the connector (connecting to the RS232 link (RxD,TxD, GND)) the radio
modem automatically switches to service mode and the SCC0 disconnects.
Important
ATTENTION! The service mode is not suitable for normal operation.
Table 3.5. Table of service connector connections
1 AF_OUT Output of modulation from radio
2 SER_RxD RS232 RxD according to standard RS232
3 SER_TxX RS232 TxD
4 MOD_BSB Input modulation to radio
5 GND Ground
6 PTT Transmitter ON
Figure 3.1. Service connector connections
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Figure 3.2. View of radio modem — description of connectors, model with DSUB
(Canon) connectors and with terminalsO
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4. Table of Technical Parameters
Table 4.1. Table of technical parameters
TYPE EU USA
Frequency range MR400: 380 – 470 MHz
MR300: 290 – 380 MHz
MR160: 136 – 180 MHz
406 – 412 MHz, 421 – 512 MHz
Channel spacing 25 kHz or 12.5 kHz
Method of setting the working frequency Software in the range 3.2 MHz
MTBF (mean time between failures) 60 000 hours
Switching time transmitting/receiving < 1.5 ms
Operating range of temperature -25 to +55 °C
Nominal supply voltage 13.8 V
Supply voltage range 10.8 to 15.6 V
Consumption Receiving 380 mA (eth. module +40 mA, I/O module +50 mA)
Transmitting 1.6 A / 1 W, 2.0 A / 5 W
Mechanical dimensions 208 × 108 × 63 mm (including DIN rails 71 mm)
184 × 108 × 63 mm (short version)
Weight 1.30 kg
Antenna connector N – female
Receiver sensitivity for BER 10-3 Better than -107 dBm
Output performance software adjustable 0.1 – 5 W
Max. speed of modulation for transmitting 21.68 kbit/s in channel 25 kHz
10.84 kbit/s in channel 12.5 kHz
Optional modules
1. a 2. slot – 1×RS232 galv. sep. or unseparated, or
1×RS422/RS485 galvanically separated
3. slot – 2×RS232
4. slot – Ethernet 10/100 Mbps
5. slot – input outputs (analog and digital)
COMPLIES WITH STANDARDS
Radio parameters
EMC (electromagnetic compatibility)
Electrical safety
Use in mobile environments
FCC PART90 406 – 412 MHz, 421 – 512 MHz
RSS119 406 – 412 MHz, 421 – 512 MHz
ETSI EN 300 113-1 V1.4.1:2002 380 – 470 MHz
ETSI EN 301489-5 V1.2.1:2000
CSN EN 60 950:2001
UN Regulation No.10 (EHK No.10)
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5. Dimensional Diagram
Figure 5.1. Mechanical dimensions of MR400
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6. Labelling Radio Modems
Figure 6.1. Serial codes of products
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7. Conditions for MR400 Operation
Radio modem installation and maintenence
Radio modems MR400 (MR300, MR160) shall always be installed by personell who have been trained by RACOM or
by an authorised representative of RACOM. Information contained in the documentation, including this manual, can not
fully substitute the training required. MR400 as such does not require any regular maintenance when properly installed.
A functional wireless data network, however, does require permanent maintenance/management performed by qualified
and trained personnel.
RACOM and/or its authorised partners around the world provide both the training and technical support necessary.
When a remote access to the networkis enabled by the customer, the majority of maintenance issues can be handled
directly by RACOM's technical support team.
Important:
CAUTION!
The installation may contain a rechargeable backup battery. When replacing the old battery, a correct type of
rechargeable battery must be used. Otherwise there is a risk of explosion. Follow the manufacturer's instructions for
handling used batteries.
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Conditions of Liability for Defects and
Instructions for Safe Operation of Equipment.
Please read these safety instructions carefully before using the product:
•In order to comply with FCC's RF exposure limits for General Population/Uncontrolled Exposure, the antenna
used for this device must be fixed-mounted on outdoor permanent structures and must not be co-located or
operating in conjunction with any other antenna or transmitter.
•Liability for defects does not apply to any product that has been used in a manner which conflicts with the
instructions contained in this operator manual, or if the case in which the radio modem is located has been
opened, or if the equipment has been tampered with.
•The radio modem can only be operated on frequencies stipulated by the body authorised by the radio operation
administration in the respective country and cannot exceed the maximum permitted output power. RACOM is
not responsible for products used in an unauthorised way.
•Equipment mentioned in this operator manual may only be used in accordance with instructions contained in this
manual. Error-free and safe operation of this equipment is only guaranteed if this equipment is transported,
stored, operated and controlled in the proper manner. The same applies to equipment maintenance.
•In order to prevent damage to the radio modem and other terminal equipment the supply must always be
disconnected upon connecting or disconnecting the cable to a radio modem data interface. It is necessary to
ensure that connected equipment has been grounded to the same potential. Before connecting the supply cable
the output source voltage should be disconnected.
•When using rechargeable batteries as back-up supplies manufacturers instructions for these rechargeable
batteries should be adhered to at all times.
•Upon disposal of the radio modem at the end of its service life regulations related to the disposal of electronic
equipment must be adhered to.
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Declaration of Conformity
RACOM s. r. o. hereby declares that its radio modem MR400 (MR300, MR160) product complies with the basic
requirements and other respective measures of regulation 1999/5/EC. This equipment therefore bears the CE marking.
The warning exclamation mark in the circle marks the radio modem as class 2 equipment denoting radio equipment with
possible limitations or with requirements on authorisation to use radio equipment in certain countries.
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Limitations of Use.
The MR400 radio modem has been developed for the frequency range 380 – 512 MHz. Specific Specific subranges are
approved to be used in each country or region. A radio modem user must keep in mind that this radio device cannot be
operated without the permission of the respective local radio spectrum administrator who provides a specific frequency
for use and issues the appropriate permission for this.
Important
Users of MR400 radio modems in North America must be aware that because the 406.0 – 406.1 MHz
frequency range is reserved only for the government the use of radio modems on these frequencies is strictly
forbidden without proper permission.
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DISCLAIMER:
RACOM s. r. o.
(hereinafter referred to as RACOM) is the exclusive owner of all rights to this operator manual. All rights reserved. Any duplication
of this manual in any way, shape or form, or translation to any other language (without the prior written consent of the owner of the
rights) is strictly forbidden. RACOM retains the right to make changes to the technical specification or functions of this product or to
terminate production of this product, or to terminate service support of this product without advance written notice to the customer.
RACOM firmware is available free of charge. Source code is the property of RACOM and is not available to any user. Any
commercial use of the software with this licence is strictly forbidden. Changes to software and documentation are forbidden.
RACOM firmware is released with the intention that it will be useful, however without any specific guarantees. Under no
circumstances is the author or any other company or person responsible for incidental, accidental or related damage arising as a
result of the use of this product. RACOM does not provide the user with any form of guarantee containing assurance of the
suitability and applicability of the product for any particular purpose. RACOM products are not developed, designed or tested for
use in applications which directly affect the health and life functions of humans or animals and RACOM does not provide any
guarantee if company products are used in such applications.
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