DMT’s Fog Monitor (FM-120) is a cloud-particle spectrometer designed for use during ground-based or tower-based studies. This robust and weather-resistant instrument has been designed with a solid-state laser diode and compact surface-mount electronic technology.

The FM-120 allows for computation and real-time display of particle concentration, median volume diameter (MVD), equivalent diameter (ED), and liquid water content (LWC).

In addition, the FM-120 monitors multiple housekeeping variables: the number of DOF rejected particles, baseline voltages, static pressure, differential pressure (to determine True Air Speed (TAS) rate in the sample tube), ambient temperature, laser diode current, and laser diode monitor.