Decode IDM 50 Modem

IDM50 is a frequency shift keyed modem for asynchronous data transmission in 300-3400 Hz voice band. It uses binary frequency modulation techniques which make it highly immune to interference and noise and permit extensive voice-band communication link utilization.

The modem supports CCITT R.38A, R.38B and V.23 communication standards. Table of programmable channels depicts possible utilization of audio band. The modem can operate in half or full-duplex, point-to-point or point-to-multipoint mode, with receive and transmit channels independently set.

The modem employs advanced microprocessor technology, thus offering high service flexibility through programmable features. Software configuration is performed via Hayes AT command set. AT commands can be initiated from any terminal application using RS-232 communication interface. Additionally, for easy firmware upgrade a bootstrap loader is provided.

Application

IDM50 is designed for use in SCADA systems mainly based upon power utility communication networks. It can communicate through specialized, private or leased lines, radio links and power lines (PLC).

Mounting Types

IDM50 is available as a desktop modem or in two different types of standard 19'' rack:

1U rack with 1, 2 or 3 modems per rack;

3U rack with 10,12 or 14 modems per rack and additional blank front plates covering unused slots.

*All connectors at the rear side are accessible at the back openings.

Operation
Type	Data transmission on band share audio frequency analog medium.
Modulation	Bivalent frequency shift of the significant frequencies centered at one quarter and three quarters of the channel.
Media	LS (Specialized Line), Radio, PLC
Mode	Full duplex: on same channel when modem is configured as 4W on different channels when modem is configured as 2W Half-duplex: on same channel when modem is configured as 2W on a half-duplex radio link or semi-duplex equipment
BER	Better than for a signal/noise ratio of 17dB with a group delay distortion of 60% whatever the channel.

Interfaces
DTE interface	RS-232C, DB9 (female) connector Signals: DCD, RD, TD, DTR, SG, DSR, RTS, CTS, RI Character length: 5-9 data bits, 1 start, 1 stop RTS/CTS delay: adjustable by 1ms step within range of 40-6825ms Option to switch on fail relay if DCD off Option to transmit on RTS Option to copy DSR to DTR Configuration: AT command set at 1200 bps
Analog line	DB15 (female) connector; 600Ω or high impedance with return loss < 0.2; Transmission level: 0 to -32dBm, programmable by 1dB step Receive level: 0 to -36dBm, programmable by 1dB step, min. -48dBm Radio control: half-duplex control and squelch detection
Power supply	2-position screw plug type (for 2-2.5mm2 wire)

General
LED indication	PWR, TXD, RXD, DCD
Power supply	36-72VDC, 25-50VAC
Isolation	Transformer up to 1500V
Immunity to noise	Peak pulse noise: 100V Peak Effective interference at 50 Hz: 80V rms
Temperature	Operation and storage: -10? to +50?C
Dimensions	desktop: aluminium enclosure 112x30x170mm 19'' rack: EUROCARD PCB, 160x100mm 3HE, 6T in 1U and 3U rack