The FAC-R frequency-to-analog converter changes incoming sensor frequency to both current and voltage analog output. The converter interfaces with a variety of frequency-out sensors and instrumentation, including flowmeters, tachometers, pumps, motors and linear/rotational encoders. A Bluetooth communication interface supports both basic scaling and advanced functions using a tablet or smartphone, such as linearization table programming that helps improve output of nonlinear devices or extend the range of a flowmeter beyond its linear range. With the Bluetooth mobile application on a smartphone, users have a wireless flow monitor in their hands. Operators can use the Bluetooth capability on a mobile device for remote setup, troubleshooting and reconfiguration.