Description
The EFME is the smallest radio base station of our wireless system: a USB stick that establishes the radio link to the transmitter modules. No cable, no external supply — power comes from the USB port. This lets you set up, calibrate and monitor wireless measurement from any Windows computer or tablet. The EFME is compatible with existing T24 systems.
The module transmits and receives. This provides error detection and correction over the radio link, configuration and calibration of the transmitters by radio and their remote control from the computer. Despite its small size, the EFME can be used with all transmitter modules of the system.
Two points belong in the planning: the free Toolkit software must be installed before the stick is plugged in for the first time, as it brings the drivers. And only one USB base station of this type works per computer — if several base stations are needed on one computer, a base station with its own interface is the right choice. The base station monitors one radio channel; all modules must be on the same channel. The bandwidth is sufficient for about 200 readings per second per channel, and mixed sensor types are possible.
The radio link uses the licence-free 2.4 GHz band with DSSS at 10 mW transmit power. The range of up to 500 m applies in line of sight in open field at 3 m height. The EFME itself needs no calibration — it calibrates the other devices of the system.
Benefits at a glance
- Smallest base station of the wireless system, powered solely via USB, no wiring
- Built-in antenna, line-of-sight range up to 500 m
- Configuration, calibration and monitoring of all transmitter modules
- Supply 4.875 to 5.125 V DC per USB 2.0, current consumption below 100 mA
- IP50 protection, dimensions 58 × 20.5 × 11 mm
- Operating temperature −20 to +55 °C, storage −40 to +85 °C
- 2.4 GHz DSSS, 10 mW, licence-free
- CE, FCC and IC approvals
- Mobile logging possible with free logging software
Matching transmitter modules and displays can be found under wireless measurement, other evaluation electronics under measurement electronics.