Abstract: An acoustical analyzer system analyzes the operating characteristics of an acoustical device by operator selection of frequencies and amplitudes of test tone signals, automatically generating test tone signals representative of the selected frequencies and amplitudes and driving the acoustical device thereby to produce output signals from the device, sampling the output signals, generating sampled signals representative of the output signals, applying Fast Fourier Transform analysis to the sampled signals to generate readout signals therefrom and operating readout means via the readout signals to display the operating characteristics of the device.

Abstract: An automatic transient response analyzer system takes advantage of a digital computer and circuitry controlled thereby to measure the time that a device under test takes to come within specified limits of a final output when driven by a signal which stepwise increases or decreases in amplitude by a known amount.

Abstract: A pulse generator for providing timed pulses of adjustable amplitude and constant width for nerve stimulation at selected portions of a body. The timed pulses of positive and negative amplitude are generated alternatively and the period can be precisely set.