Princeton Applied Research 189

The 189 Selective Amplifier is a versatile low-noise, low-distortion selective amplifier / oscillator that simultaneously provides you with tunable bandpass, notch, low-pass and high-pass amplification characteristics. Front panel controls enable you to set the bandpass / notch center frequency and the low-pass/high-pass corner frequency to any point within the amplifier's 0.1Hz to 110kHz operating frequency range. Another control enables you to vary circuit "Q" from 1 to 100 to provide the bandwidth required in your application.