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Talk:Roofing filter

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Latest comment: 11 years ago by David spector

But why is it called a roofing filter? Where did the name come from?

Answer:

A roofing filter can be thought of as protection over all the other filters in a specific input stage of a radio, protecting that stage from the barrage of unwanted frequencies, just as a physical roof protects an entire house from unwanted elements such as rain or snow. Frequencies in the desired range are allowed to pass through the roofing filters to be processed further by more specific filters. Eliminating undesired frequencies prior to more specific filtering allows for fewer unwanted processing byproducts and a cleaner, more accurate desired signal.

[1] The ARRL Extra Class License Manual for Ham Radio, Ninth Edition, 2008, Ward Silver N0AX, p. 8-21

Jgzimmerman (talk) 22:42, 29 May 2009 (UTC)Reply

Is there any reason not to add this useful information to the article? David Spector (talk) 10:07, 19 November 2014 (UTC)Reply
  1. Cite error: There are <ref> tags on this page without content in them (see the help page).