File:Norton Mechanical Filter.png
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- 2009-06-25 22:30 Spinningspark 715×498× (35668 bytes) {{Information |Description=A mechanical filter designed using electrical network theory |Source=US patent US1792655 |Date=31st May 1929 (filed) |Author=[[Edward Lawry Norton]] |other_versions= }} == Licensing == {{PD-US-patent}} {{KeepLocal}}
