HEATKEYS

Tests your audio equipment, speakers, room acoustics and hearing. Audio signals and test tones playable online. High resolution sound test files available for free download.

The web site of The Johns Hopkins University, a world-class university in Baltimore, Maryland, offering undergraduate and graduate degrees.

Indiana University is a leading research and teaching institution and one of the best values in public education according to Kiplinger

A site for people who think. Intellectual resources, programming, astronomy, science, mathematics, Java applets, HTML instruction, home of Arachnophilia.

Education projects with a focus on effective pedagogies, geoscience education, community organization, workshop leadership, digital libraries, website development and program and website evaluation

Fourier Series, Fourier Transform, Laplace Transform, Z transform, Butterworth, Chebyshev and elliptic filters, IIR and FIR Filters, P, PI, PD and PID Controllers, Root Locus, Circuit Analysis and Circuit Simulation with spice