(You are trying to measure a three terminal waveform with a two terminal device) Thats why we use dedicated ECG monitors instead of oscilloscopes
I think you will find an ECG lead is a 2 terminal thing, the third electrode is there for noise cancellation.
Lead I RA - LA
Lead II RA - LL
Lead III LA - LL
etc
So it is easy to measure on a scope.
But why all this tech talk and complication? To convert BPM to Hz divide by 60 as has been said above, or to covert Hz to BPM multiply by 60.
Set the function generator to a frequency in Hz multiply this by 60 and the reading should be that in BPM. Simples!
Why are you checking this out of interest? Are you suspecting an error in a timing circuit? The most likely cause of incorrect BPM reading is incorrect detection of the QRS spike.
Robert
