A constant-temperature hot-wire anemometer circuit using a new low noise and large frequency bandwidth operational amplifier is described. Dynamic tests showed that the circuit response was as fast as a commercial unit. Further measurements in various classical turbulent flows with hot wires and hot films, in air and water, proved the new circuit to have identical spectral behavior and comparable noise levels with much simpler design and lower cost. In addition, the design of the circuit includes convenient features such as internal square wave test, digital resistance dial for a wide range of overheat settings, and compensation for two cable lengths.