The Krohn-Hite Model 6900B is the first and only fully automatic Distortion Analyzer to provide an easy solution to your distortion and AC voltage measurements over the frequency range from 5Hz to 1MHz. The 6900B requires only an input signal. Auto frequency nulling, auto level setting and auto-ranging of the digital meter automatically displays the total harmonic distortion (THD). (read more)

The Krohn-Hite Model 6620 provides precision phase measurements with a typical accuracy of 0.02° and resolution of 0.01°. It will accept a wide range of input signal levels from 10mVrms to 320Vrms and input waveforms including sine, triangle, square and pulses. A 5 digit LED display provides continuous direct readout of phase angles between 0.00° and 360.00° or ±180°. (read more)