With a 500-mW (+27 dBm) RF output power and a receiver sensitivity of –118 dBm (for 12 dB SINAD), the BHX2 multi-channel narrowband transceiver sports a range of up to 5 km. Standard operating frequency is 458.5 to 459.1 MHz, but factory-tuned custom versions can cover any 5 MHz switching band between 420 and 480 MHz. The transceiver’s 25-kHz channel spacing allows a total of 128 channels, configurable via an RS-232 interface. Using a supply voltage of 5.5 to 15 V, the BHX2 draws 350 mA while transmitting and 30 mA for receiving. The module offers a 5-kbit/s data rate and incorporates a 1200-baud half-duplex modem that is compatible with that used by the company’s other devices. An automatic noise squelching function activates when there is no RF at detectable levels or when the non-coherent noise is high enough to block out weak signals. The module comes in an 85- by 39- by 13-mm package and conforms to both the EN 300 220-3 and EN 301 489-3 standards. RADIOMETRIX LTD., Harrow, UK. +44 (0) 208-909-9595.