The Models 3200 and 3202 are solid state variable electronic filters with cutoff frequencies continuously adjustable over the frequency range from 20 Hz to 2 MHz. The pass-band gain is unity (0 db), with an attenuation rate of 24 db per octave outside the pass-band. Maximum attenuation is greater than 80 db and the output hum and noise is less than 100 microvolts. The Model 3200 can function as either a High-Pass or Low-Pass Filter. In the High-Pass mode of operation the maximum input signal is 3 volts rms and the upper 3 db point occurs at approximately 10 MHz. In the Low-Pass mode the Filter is direct-coupled and the combined ac plus dc input signal should not exceed 4,2 volts peak. The Model 3202 consists of two Model 3200's mounted in a single cabinet isolated from each other with independent power supplies, and input and output connectors. When these two filter channels are switched to the same mode of operation and connected in series with both dials set to the same cutoff frequency, the Model 3202 will function as a High-Pass or Low-Pass Filter with an attenuation rate of 48 db per octave. If the two channels are connected in series, and one channel is operated in the Low-Pass mode and the other channel a the High-Pass mode, the Model 3202 will function as a Band-Pass Filter with attenuation rate of 24 db per octave outside the pass-band.