The anemometer cup rotation produces an AC voltage signal with a frequency directly proportional to wind speed. Wind speed is measured in meters per second. Wind vane position is transmitted by a precision conductive plastic potentiometer. The output signal is an analog voltage directly proportional to the wind direction azimuth angle. The Tipping Bucket Rain Gauge is an adaptation of the standard Weather Service tipping bucket rain Gauge.
Output is a switch closure for each bucket tip.
A multiplier in the datalogger program determines the units in which rainfall is reported. Rainfall is measured in millimeters. Barometric pressure is calculated from the measured output voltage using a simple equation. Pressure measurements are reduced to sea level. Barometric pressure is reported in millibars.