PLL_LOCK RDF TDF RX_EN TX_EN HSD_RX HSD_TX POWER SD-250NTG User Guide
April 4, 2011 SD250 NTG – USER GUIDE Contents Introduction --- 2 Preparing for use Unpacking and inspection --- 3 Description of modem --- 4 Features --- 5 External Connections --- 6 Pin Outs --- 7 Operation Program Radio --- 8 Transmit/Receive Operation --- 9 Status Indicators --- 10 Installation Antennas --- 11 Power sources --- 11 Cabling --- 12 Fixing --- 12 Safety and general information --- 13 Warranty and repairs --- 15 Care of the equipment --- 15 Disposal / Recycling --- 15 Midland Radio Corpora
April 4, 2011 SD250 NTG – USER GUIDE Introduction The SD250NTG range is a 0.5 to 5 Watts RF data module at UHF frequencies. The SD250NTG is housed in a rugged cast-aluminum box sealed to IEC 529 (IP54) making it suitable for a wide range of mobile and fixed applications. The SD250 RF data module unit meets the essential requirements of the relevant directives. In order to maintain this compliance the installation and safety information must be adhered to at all times.
April 4, 2011 SD250 NTG – USER GUIDE Preparing for use Unpacking and inspection Unpack the modem and check that you have received the following items: • SD250NTG RF data modem • User Guide (this document) If any of these items are missing, please contact your supplier.
April 4, 2011 SD250 NTG – USER GUIDE Description of modem The SD250NTG has been designed to be used in an advanced, highly robust, two-way fixed base meter reading solution that delivers comprehensive usage information through a secure, long-range wireless network. The SD250NTG is a network free, point to point RF data modem that offers great flexibility in varied applications where wireless data is needed. The modem supports 7,200 baud GMSK modulation over the narrow band channel spacing, 12.
April 4, 2011 SD250 NTG – USER GUIDE Features • Compact and rugged die cast box • Resistant to dirt, dust and water ingress (IP54 rated) • Network free, point to point communication • 0.5 - 5 watt programmable output power • Synthesized operation • 12.
April 4, 2011 SD250 NTG – USER GUIDE External Connections PLL_LOCK RDF TDF RX_EN TX_EN HSD_RX HSD_TX POWER 1. HD 15-way d-type (data, control signals and power supply) 2.
April 4, 2011 SD250 NTG – USER GUIDE Pin Outs DB-15 PIN OUT table with input and output levels D-Type Pin No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 Function Description Signal Type DCD RXD TXD DTR GND DSR RTS CTS RI AUDIO OUT GND +12V GND AC1 AC2 Data Carrier Detect Received Data Transmitted Data Data Terminal Ready Ground connection to chassis of the radio. Data Set Ready Request To Send Clear To Send Ring Indicator Discriminated audio output Ground connection to chassis of the radio.
April 4, 2011 SD250 NTG – USER GUIDE Operation Radio program Frequencies for receiver and transmitter are programmed by R450 Radio Diagnostic program. The program also allows for RSSI and Radio calibration, includes TX power output, Frequency error, FM modulation/balance and RX DCoffset cancellation.
April 4, 2011 SD250 NTG – USER GUIDE Transmit/Receive Operation The SD250NTG is put into transmit/receive by using RS 232 leveled data. The radio is controlled by existence of inputted data from a DTE. The data to be transmitted is automatically stored while the transmitter is turned on and transmitted after finishing preparation for transmission. When the radio receives valid information over the air, then it is sent out to the data terminal.
April 4, 2011 SD250 NTG – USER GUIDE Status indicators The LED indicates the current status.
April 4, 2011 SD250 NTG – USER GUIDE Installation Antennas It is important that any antennas are installed in a suitable location with an adequate ground plane. Ideally, multiple antennas should be separated by a minimum of a wavelength (at the lowest frequency), whilst still retaining a good ground plane for each antenna. Therefore, for a 400MHz system, the ideal separation should be a minimum of 0.75m.
April 4, 2011 SD250 NTG – USER GUIDE Cabling If possible, run RF cables separately from other cables and keep RF cables apart from one another to avoid interference / coupling. When fitting the modem into a fixed installation care must be taken in the routing of all cabling such that the insulation cannot become damaged. Fixing We recommend that the SD250 is securely fixed to a surface, either directly, or with a suitable bracket. The fixing hole center dimensions are as shown.
April 4, 2011 SD250 NTG – USER GUIDE Safety and general information Important information on safe and efficient use of your Radio device Exposure to radio frequency energy Your modem is a high power radio transceiver. When it is on, it receives and also sends out radio frequency (RF) signals. To help minimize human exposure to RF electromagnetic energy, keep transmission time to 50% or less.
April 4, 2011 SD250 NTG – USER GUIDE Vehicles with airbags Air bags inflate with great force. Do not place a radio in the area over an airbag or in the airbag deployment area, any radio may be propelled with great force and cause serious injury to the occupant of the vehicle. Potentially explosive atmospheres Turn off your modem prior to entering any area with a potentially explosive atmosphere, unless it is a radio type especially qualified for use in such areas.
April 4, 2011 SD250 NTG – USER GUIDE Warranty and repairs The SD250 is a low maintenance device. Once installed it requires no ongoing maintenance. In the event that your SD250 RF data module needs repair, return your radio to an authorized Midland Radio supplier. Do not disassemble, modify or repair the unit unless the work is carried out by a Midland Radio approved supplier. Incorrect assembly, modification or repair may cause irreparable damage to your unit and will invalidate any warranty.
April 4, 2011 SD250 NTG – USER GUIDE Published by Midland Radio Corp. Any queries regarding information in this manual, please contact the Technical Services Group Leader at the above address. Information provided in this document is believed correct at time of printing but is subject to change without notice. Midland Radio will not accept liability for any loss, damage or costs howsoever caused as a result of the information provided.
