PROEL DSO480 - Bandpass Filter; Notch Filter

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Bandpass Filter
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InA Input A BPS:1/\
1k00Hz Q=3.0 Bandpass
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Remember–tochangefiltertypes,pressBYPASSto
bypassthefilter,andthenuseENTERtoselectthefilter
type.
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Thebandpassfilterhasadjustablefrequencyand‘Q’(or
Bandwidth)controls.Theseaffectarangeoffrequencies
symmetricallyaboutthecentrefreqencyasshowninthe
graph,graduallycuttingth
elevel,butprovidingnogain.

Rememberthat‘Q’is1/Bandwidth,sothehigherthe
‘Q’,thelowertheBandwidth,andthesmallertherange
offrequenciesaffected.
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NotethattheresponseisfundamentallyNOTaflat‐toppedresponse(soitisnotconstructedfromahighpass
andlowpass).Se
epreviouspagefordetailsofhowtoconstructaflat‐toppedfilterresponse.
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Notch Filter

InA Input A NOT:1\/
1k00Hz Q=0.75 Notch

Remember–tochangefiltertypes,pressBYPASSto
bypassthefilter,andthenuseENTERtoselectthefilter
type.

Thenotchfilterhasadjustablefrequencyand‘Q’(or
Bandwidth)controls.Theseaffectarangeoffrequencies
symmetricallyaboutthecentrefreqencyasshowninthe
graph.

Reme
mberthat‘Q’is1/Bandwidth,sothehigherthe
‘Q’,thelowertheBandwidth,andthesmallertherange
offrequenciesaffected.Thenotchfilterdepthvaries
withbandwidth–thewiderthefilter,thelowerthe
depthwillbe.
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