Post History
When recording an ECG signal, the raw signal is taken from the body and sent into an ECG amplifier to amplify the signal to a suitable range and remove common mode and other types of noise. Measur...
#2: Post edited
by
Lorenzo Donati
·
2023-08-10T17:09:46Z (over 1 year ago)
Retagged.
#1: Initial revision
by
Carl
·
2023-06-12T20:12:31Z (over 1 year ago)
Why do I need electrodes for ECG measurements?
When recording an ECG signal, the raw signal is taken from the body and sent into an ECG amplifier to amplify the signal to a suitable range and remove common mode and other types of noise. Measuring the raw ECG signal is done by placing pre-gelled electrodes onto both wrists and one reference electrode on the right leg. The wires connected to the electrodes placed on the wrists are connected to the input terminals of an instrumentation amplifier. So essentially, I am measuring and amplifying the voltage difference between my wrists. But why exactly do I need electrodes to make this measurement? Why can't I just have two isolated wires touch my wrists and connect those to my in-amp? Why does the interface between my skin and the electrode have to be gelled?