The HX1 from Radiometrix is a narrow band VHF radio transmitter module designed for use in various data-transfer applications. When used in conjunction with the matching RX1, BiM1R, or CVR1 receiver modules, a one-way radio data link can be created that can span distances of over 10 km. The radio module produces a 300-mW (24.7 dBm) RF output, supporting a maximum data rate of 3 kbits/s, and has a frequency placed within the 169-MHz European license exempt band, though it's available with all transmit frequencies in the 120- and 180-MHz band. The device has a modulation bandwidth of 0 to 3 kHz at -3 dB. It runs from a standard 5-V regulated supply, and typically draws less than 140 mA. Suitable applications include asset tracking or non-contact meter reading systems, as well as paging devices, data logging, and high-end security/fire alarms systems. More information is available at www.radiometrix.com.