Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!thunder.mcrcim.mcgill.edu!snorkelwacker.mit.edu!usc!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!midway!gargoyle!igloo!ddsw1!olsa99!frcs!paul From: paul@frcs.UUCP (Paul Nash) Newsgroups: sci.electronics Subject: Re: A question about the Nyquist theorm Message-ID: <386@frcs.UUCP> Date: 18 Feb 91 16:26:27 GMT References: <1991Feb17.115102.15399@Neon.Stanford.EDU> Organization: Free Range Computer Systems CC Lines: 18 Thus spake terryb.bbs@shark.cs.fau.edu (terry bohning): > zimmer@calvin.stanford.edu (Andrew Zimmerman) writes: > > Just to nit-pick, it should be "GREATER then twice the bandwidth of the > > signal", not twice the highest frequency. > > Wow, that's great! So I only need to sample my 10 Hz bandwidth signal > which is centered at 1 MHz at 20 Hz! Correct! Now all you need to do is to pass the reconstructed analogue output through a 1 MHz +/- 10 Hz bandpass filter (with infinitely fast roll-off), and you will have a 10 Hz signal centred on 1 MHz. The amplitude might be a bit low, but it will be there. Try reading about it -- it _does_ work. ---=---=---=---=---=---=---=---=---=---=---=---=---=---=---=---=---=--- Paul Nash Free Range Computer Systems cc paul@frcs.UUCP ...!uunet!m2xenix!frcs!paul Brought to you by Super Global Mega Corp .com