Elsie 2.80 can be downloaded from our website for free. The program belongs to Education Tools. The actual developer of the software is James L. Tonne.
From the developer:
Elsie ™ is an uncommon commercial-grade lumped-element ("L-C") electrical filter design and network analysis program, directed toward the engineer, technician or hobbyist involved in that line of work.
Elsie is 32-bit Windows® electrical filter design software nicely written to help engineers design and analyze lumped-element filters in the audio through microwave range.
You may want to check out more software, such as SRIM, StatPlus or EarthBrowser, which might be similar to Elsie.