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Digital filter question [message #3002]

Tue, 01 November 1994 03:45

larkum
Messages: 21
Registered: May 1993

Junior Member

I can't understand description of DIGITAL_FILTER in the PV-Wave
manual. I have some data with an annoying 50Hz mains signal that
I'd like to try to filter out. The manual talks about the Nyquist
Frequency as 1/2T, where T is the time elapsed between data samples.

Well, I have data sampled at 20 kHz, so as far as I can tell,
the Nyquist frequency for this data is 10 000. Am I right?
Now what? (besides read a book on digital signal processing).
What should my low and high frequencies be to set a bandpass
filter around 50 Hz, expressing them as "fractions of the
Nyquist frequency" as "numbers between 0 and 1".

Thanks anyone,

Matthew.
____________________________________________________________ ______________
Matthew Larkum
Physiologisches Institut
Buehlplatz 5, CH-3012 Bern Switzerland
Ph. 41 31 658726 Fax. 41 31 654611
Internet: larkum@optolab.unibe.ch
matthewl@cortex.physiol.su.OZ.AU

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[Message index]

		Digital filter question By: larkum on Tue, 01 November 1994 03:45
		Re: Digital filter question By: sgs on Fri, 04 November 1994 12:49
		Re: Digital filter question By: alps on Fri, 04 November 1994 06:25
		Re: Digital filter question By: soc on Thu, 03 November 1994 09:38

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