The DewTrak II MO specific humidity and barometric pressure transmitter is a chilled mirror dewpoint hygrometer that continuously measures the moisture content and barometric pressure in the motor octane testing process. It is used to monitor and ensure compliance with test standards ASTM D2700, D2699, D2885. NIST traceability guarantees measurement compliance for the allowable specific humidity and the pressure ranges.

The DewTrak II MO is powered by 24 Vdc and can be easily fitted to existing knock engine systems. It is a custom tailored system for measuring conditions required for Motor Octane Number (MON) and Research Octane Number (RON). It uses a chilled mirror dewpoint temperature sensor to accurately determine the specific humidity and a pressure sensor to measure the barometric pressure of the motor intake air fuel mix.