900-MHz Transceivers Deliver 20+ Mile Range March 2005 Issue Published Date: March 09, 2005
Adding to the SEM and HopNet 900-MHz transceivers are long-range versions that provide 500 mW of transmit power and a receive sensitivity of -104 dBm. Using omni-directional antennas with a clear line of sight, the components are capable of transmit and receive distances in excess of 20 miles. The ability to achieve this range without using directional antennas promises to eliminate the costly and time-consuming need to aim the antennas. Designed to provide connectivity between Ethernet devices, the SEM 910 family includes the SEM 910, SEM910X, SEM910D, and SEM910DX. The HopNet family, consisting of the HN-291, HN-291X, HN-291D, and HN-291DX serial and Modbus modems with built-in antennas or external connectors, provide wireless connectivity between serial devices. Both deliver an over-the-air data rate of 172.6 Kb/s. CIRRONET INC., San Diego, CA. (678) 684-2000.
