Hartcran House, 231 Kenton Lane, Harrow, Middlesex, HA3 8RP, England Tel: +44 (0) 20 8909 9595, Fax: +44 (0) 20 8909 2233, www.radiometrix.com Issue 2, 30 July 2012 LMT1/LMR1 VHF Narrow Band FM Low Cost multi channel radio modules The LMT1 transmitter and LMR1 receiver modules offer a 12.5kHz / 25kHz channel spacing multi channel, low power, and reliable VHF data link. This makes the LMT1/LMR1 pair ideally suited to those low power applications where existing wideband modules have insufficient range, or where low cost multi-channel operation is needed without compromising on RF specification or regulatory requirement. Figure 1: LMT1 transmitter and LMR1 receiver Features Conforms to EN 300 220-2 and EN 301 489-3 High performance double superhet. PLL synthesizer with TCXO quasi-dc (peak sampling) data recovery circuit (for enhanced performance on unbalanced datastreams) Data rates up to 5 kbps for standard module Usable range over 1km Fully screened. Low profile Feature-rich interface (RSSI, analogue and digital baseband) Re-programmable via UART interface Low power requirements Applications Handheld terminals Industrial telemetry and telecommand In-building environmental monitoring and control High-end security and fire alarms Heavy vehicle/machinery controls Technical Summary Operating frequency: 144-146MHz Amateur Radio 150.825-152.450MHz Australian LIPD Band 151.820-154.600MHz US Multi-Use Radio Service (MURS) band 156.525MHz Global Maritime Distress and Safety System 173.200 - 173.325MHz UK Telemetry, Telecommand, Fixed Alarm band 173.20375-173.39625MHz US FCC Part 90.238 Telemetry Other custom variants from 130 - 180MHz on any 2MHz band 4 UK allocation channels (32 maximum) Transmit power: +10dBm (10mW) nominal 3.1V (Adjustable 1 - 25mW) +20dBm (100mW) nominal 4.1V (Adjustable 25 - 100mW) Supply range: 3.1 15V ( 10mW) transmitter and receiver Current consumption: 34mA 10mW, 90mA 100mW (transmit) and 20mA (receive) Data bit rate: 5kbps max. (Standard module) Receiver sensitivity: -118dBm (for 12 dB SINAD) Evaluation platforms: NBEK + LM Series carrier Radiometrix Ltd LMT1/LMR1 Data Sheet page 1 Radiometrix Ltd LMT1/LMR1 Data Sheet page 2 Figure 2: LMT1 block diagram