The GM50 microphone disc is a very versatile successor of the FG-DT50 microphone from Avisoft Bioacoustics. With the built-in ultrasonic capsule Knowles FG-23629-P16, the integrated microphone heater and preamplifier as well as a 40kHz test signal speaker, it offers all the features of its bigger sister GM90 in terms of frequency response, directional characteristics, noise level, condensate avoidance and microphone sensitivity logging. In addition, due to the removable mounting plate, the microphone disc can not only be used for mounting in the floor of wind turbine nacelles, but also with the optional tripod for alternative measurements not on wind turbines. When installed in the floor of wind turbine nacelles, the GM50 is characterized by the small required bore diameter of just 55mm (Drilling Plan - GM50). It should be noted, however, that due to the lack of a wind protection ring and the changed dimensions compared to the GM90, the GM50 microphone disc is not compatible with the software tool for calculating shutdown times Probat.
To protect against weather and environmental influences, all electronic components in the aluminum made microphone disc are splash-proof encapsulated.