A40 Wireless RF Module

A40 Wireless Portable Alarm Up to a 40 node alarm system – offering alarm outputs at each location for sounder and or strobe light. An optional display indicates location of alarm activation. With the display board you are also able to detect a battery low on any unit in the system as well as battery low indication on each node via an LED indicator or sound indicator via an optional low battery sounder board. The whole system can be battery operated for 6 months on an Alkaline “C” cell pack.



This is a mesh networking system using Mini MURS technology. So it can cover approximately a 2 to 3 km range in a 4 hop system.


  • Temporary fire alarm – this is ideal for remote building sites, showground alarms or anywhere a temporary alarm system is required.
  • Multi- building alarms– the unit can be hard wired or battery operated to offer a permanent solution for multi- building alarm systems.
  • Door alarms in buildings – exit doors which need to be alarmed can transmit back to a central display unit with the door ‘number’
    being displayed.
  • Fence alarms – with the use of gain antennas the system could be used for border or perimeter guarding and ranges of several kilometres
    could be achieved to guard areas along with ‘ fill in’ units along the fence to give precise location of intrusion.
  • Medical alarm in hospitals/ care home – units could be attached to ‘out of bed’ alarms for elderly patients. With
    display units positioned on walls to show which bed had been vacated to nursing staff.
  • Classroom emergency alarm- Could be used in schools with a display on each node so that teachers in trouble could be alerted if a
    fellow teacher was in an emergency situation. Each node would give location of alarm.
  • Light switching – could be used to turn all lights on in a carpark if movement was detected and a simple circuit used to turn off
    again after a period. Using expanded mode up to 400 lights could be controlled and turned on / off.



  • Single input for alarm IN
  • Test mode input
  • Clear alarm input
  • Two outputs – one relay for switching up to 240V (Lights, Alarms)
  • Second output is a ‘supply volt’ switched DC output
  • Mesh network 4 hop system
  • Category 1 receivers ensuring maximum compliance for safety applications.
  • 4 second local mode alarm output trigger ( 60 second full system)
  • Battery powered – very low power consumption.
  • Lost units can be detected and reported via serial port.
  • Serial output on each board which could be connected to a PC or alarm panel for greater functionality. (a conversion board to allow communications
    in a format for any alarm system is available)


The system can be expanded:

The basic system has 40 nodes – however these can have another 10 satellite units attached to each node.
The satellite units are given the same number as the node so cannot be distinguished as individual units for the purpose of identification but allow and
‘area’ to be detected. A typical use of this would be in a fire alarm where you wanted smoke detectors around an area (500m radius) around a node which
then communicated on to the rest of the network. Satellites are mainly therefore used to ‘report in’ an alarm. There is also an option for ‘listen only’
units which can be positioned anywhere in the system and just listen. If there is an alarm they will sound, if a sounder is connected to the output. These
units are called Drones. A drone could be used as a display unit if optional display board is attached.

For more information please email any questions to: sales@lemosint.com

Please Note Disclaimer:

Lemos International does not assume any responsibility for errors nor any liability arising from the application or use of any sub-assemblies purchased through Lemos International, including fitness for any particular application.

The purchaser must satisfy all relevant FCC and Radio Regulations which applies to their finished product in the country of intended use. These modules transmit and/or receive radio signals and may not function as intended if interference is present.

Downloads & Datasheets

A system consists of main boards A40 and a display board A40D. The main board can be configured as:

Master – numbered 00 – one per system this is the main unit giving out timing pulses but is also a working unit.

Node– numbered 01 -39 these are the back bone of the system enabling meshing – Drones & Satellites do no mesh.

Drone – numbered 41- these receive only and are used as sounders or perhaps displays attached

Satellite – These are attached to nodes to expand the system and are numbered the same as the node with a special link across two
pins to enable this mode.

The display can be attached to any of the above to enable it to display status.

  1. Full Specs PDF




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