When frequency is selected as the wind speed analog output, WMT700 sends a pulsed signal of 0 to 10 V with a frequency proportional to wind speed through AOUT1. Every mile per hour adds 5 Hz (WS425) to the frequency. In SI units, a change of 0.894 meters per second adds 10 Hz to the frequency. A frequency counter is required to count the output in Hz and the calculation that scales the result to appropriate units.