434MHz Low Power Long Range Radio Modem (SLR-434M)

The Circuit Design SLR-434M Smart Modem - a compact, easy to use narrow-band embedded radio modem operating in the 434 MHz ISM band. It incorporates LoRa® technology to achieve extremely long range for low bit-rate data with low power.  The SLR-434M’s  excellent receiving sensitivity allows communication into areas once considered difficult for RF to penetrate, and making it possible to transmit 1800 feet or more.  The SLR-434M is also switchable to accommodate conventional FSK communication.

The SLR-434M can transmit data or operate in simple control systems using Circuit Design\'s dedicated command protocol from an external CPU or PC via an RS232 or COMport interface. The SLR-434M can process 8 I/O switching signals.  With up to 10mW RF output power from the SMA connector, the SLR-434M can be used in simplex or duplex mode on 137 channels.  It operates from a 3.5 – 5.0V supply, consuming less than 30mA when transmitting.  Its low power consumption makes battery operation possible with this sturdy 1.6” x 1.2” x 0.25” module.  

Applications include data transmission, telemetry, and control in buildings, water level and dam monitoring, tunnel and bridge condition monitoring, etc.

The TB-SLR-RS2 is an RS232 interface board for experimenting with the SLR-434M module. The built-in DB9 connector allows quick connection to the COM port of PC or PLC.  The board is equipped with transmit/receive LED, a power supply terminal, main switch and an interface to sub boards. The module can be used with a coax extension cable to allow optimum placement of the antenna according to the environment.

A descriptive video of the SLR-434M Smart Modem is here: https://youtu.be/dl3LeEf3jfE

*LoRa® is a trademark of Semtech Corporation.