12-01-2011 08:32 PM
I am a student working on an ECG project. I built a frontend similar to the example on the AD620 instrumentation amplifier datasheet. It connects to an RPI redboard 2. I am using this document as a guide to set up the signal processing:
http://zone.ni.com/devzone/cda/tut/p/id/6349
I added the first digital filter to remove baseline wandering. The input signal is 2.5V but after the filter it is only 75mV. The cardiac signal is 1 Hz. Here is the filter setup:
Can someone tell me why I am losing so much amplitude? Also, I copied a 60Hz notch filter from the ECG notch filter example that comes with the DFD Toolkit, but it has no effect on the signal. The 60Hz noise remains. I have attached my file. Any help is greatly appreciated.
12-01-2011 08:57 PM
Hi,
Could you please attach some data samples as tdms file here? I suggest you firstly have a look at the spectrum of the acquired signals.
ZJ Gu
12-05-2011 09:27 PM
This is my first time using LabView. When I connect the file io.vi to create the tdms it drastically slowed down the program and it didn't seem to acquire the signals correctly. I also installed the OOo Calc TDMS add-on to see what data it stored, but like other users it didn't create the menu item in Calc. My input signal is very clean as I am using an arbitrary waveform generator to simulate the ECG. I took a screen shot to show that the signal is nearly identical, but it is attenuated and it is inverted. What could be causing this?