----- Original Message ----- From: Marcos Migliorini To: pic microcontroller discussion list Sent: S‡bado, 27 de Marzo de 1999 09:19 p.m. Subject: Re: Re: Electrocardiogram (PIC ECG) >Tom you are rigth but think about an EEG machine...... You need a lot of >filters and also you need min 8 channels!; some EEG machines have 24 >channels. In this case is very useful use a DSP in orther to perform the >digital filter, may be one DSP/channel. >What do you think? >----- Original Message ----- >From: Thomas McGahee >To: >Sent: S‡bado, 27 de Marzo de 1999 04:01 p.m. >Subject: Re: Electrocardiogram (PIC ECG) > > >>Howard, >>As wonderful as the PIC is, it is not always the best solution for >>*all* problems. Sometimes an op amp or some other piece of hardware >>greatly simplifies the solution. >> >>An OpAmp amplifier followed by a 60 Hz active reject filter would be an >>appropriate solution. >> >>If you are interested in only signals *below* a certain frequency, >>then a low pass filter might also be added. >> >>If you are interested only in a very narrow band of frequencies, >>then a bandpass filter would do the job. >> >>Don Lancaster's "Active Filter Cookbook" has a decent treatment >>of the kinds of circuits that might be of interest to you. >> >>The use of modern single-supply OpAmps would eliminate the >>need for a negative power supply in most designs. >> >>Fr. Tom McGahee >> >>---------- >>> From: Howard McGinnis >>> To: PICLIST@MITVMA.MIT.EDU >>> Subject: Electrocardiogram (PICECG? >>> Date: Saturday, March 27, 1999 9:59 AM >>> >>> In a paper found on the web from MIT Health Sciences and Technology, it >was >>> stated that the electrocardiogram signal is approx 1 mv in amplitude. If >>> the signal is amplified, how can the 60 Hz be filtered by the PIC without >>> affecting the ECG signal? >>> >>> Howard >>> Howard McGinnis >>> hmcginni@digital.net >>> Electronic Visions, Inc. >>> 1650 Barrett Drive >>> Rockledge FL 32955 >>> (407) 632-7530 >>> http://ddi.digital.net/~hmcginni >>> mcginnis@e-visions.com >> >