•−•  ••−•    −•−•  •−  ••−•  •
RF Cafe Morse Code >Hear It<

Job Board

About RF Cafe™

Sitemap

RF Cafe Software

RF Cascade Worbook
 RF Cascade Workbook 2005 - RF Cafe
Calculator Workbook
RF Workbench
Smith Chart™ for Visio
Smith Chart™ for Excel
RF & EE Symbols Word
RF Stencils for Visio

Your RF Cafe
Progenitor & Webmaster

Click here to read about RF CafeKirt Blattenberger
BSEE
KB3UON
EIEIO

Carpe Diem!
(Seize the Day!)

5th MOB:
My USAF radar shop

Airplanes and Rockets:
My personal hobby website

Equine Kingdom:
My daughter Sally's horse riding website

Definition - RF Cafe Forums

The original RF Cafe Forums were shut down in late 2012 due to maintenance issues. Below are all of the old forum threads, including all the responses to the original posts.

-- Amateur Radio
-- Anecdotes, Gripes & Humor
-- Antennas
-- CAE, CAD, & Software
-- Circuits & Components
-- Employment & Interviews
-- Miscellany
-- Swap Shop
-- Systems
-- Test & Measurement
-- Webmaster

Antonio
Post subject: Definition Posted: Mon Nov 05, 2007 6:42 pm

Captain


Joined: Sat Jun 16, 2007 12:26 am
Posts: 12
Can anyone please define in detail about these???


1) What is the selectivity of a filter?


2) What is the mathematical expression for selectivity?






Top

jaslovkel
Post subject: Posted: Tue Nov 06, 2007 11:57 am

Captain


Joined: Tue Jun 26, 2007 10:27 am
Posts: 11
Location: Dallas, TX
Hi Antonio,

Selectivity is usually another name for how much attenuation is available in the stopband of a filter in a given frequency range. It depends on what type of filter it is to what the mathematical representation will be. This is because different filter approximations will have different transfer functions. However, the more poles in the transfer function will make the resulting circuit act as the ideal 'brick wall'. A narrowband system will require a filter with very high selectivity while a wideband system will require a low selectivity.

-J


Top

Antonio
Post subject: Posted: Fri Nov 09, 2007 3:31 am

Captain


Joined: Sat Jun 16, 2007 12:26 am
Posts: 12
Thank you very much for your help.




Posted  11/12/2012

Try Using SEARCH to Find What You Need.  >10,000 Pages Indexed on RF Cafe !

Copyright 1996 - 2016
Webmaster:  Kirt Blattenberger, BSEE - KB3UON
Family Websites:  Airplanes and Rockets | Equine Kingdom

All trademarks, copyrights, patents, and other rights of ownership to images
and text used on the RF Cafe website are hereby acknowledged.