Abstract: There is disclosed a handheld air flow velocity measurement probe that includes a bridge circuit assembly having an airflow velocity sensor that is a resistance temperature detector (RTD) and a digitally controlled resistive element to dynamically adjust and maintain the resistance of the velocity sensor within the overheat temperature predefined range. The velocity measurement also uses a separate temperature sensor to sense the temperature of the air or gas flow. A humidity sensor is also included remote from the other sensors to measure humidity in the gas flow to be measured. All of the above described components are housed at a probe tip instead of a base as in most standard handheld probes and the digital interface at the probe tip allows the user to replace a bulky, expensive telescoping antenna with stackable extender scheme.

Abstract: There is disclosed a handheld air flow velocity measurement probe that includes a bridge circuit assembly having an airflow velocity sensor that is a resistance temperature detector (RTD) and a digitally controlled resistive element to dynamically adjust and maintain the resistance of the velocity sensor within the overheat temperature predefined range. The velocity measurement also uses a separate temperature sensor to sense the temperature of the air or gas flow. A humidity sensor is also included remote from the other sensors to measure humidity in the gas flow to be measured. All of the above described components are housed at a probe tip instead of a base as in most standard handheld probes and the digital interface at the probe tip allows the user to replace a bulky, expensive telescoping antenna with stackable extender scheme.