R-wave detection:
Differentiate and look for the big spike?
or just look for the largest signal as manual mode usually uses?
Having worked in a cardiac hospital and seen P-waves bigger than R-waves it is not that simple, especially if the electrodes are either side of a huge cut down the chest.
Digital storage scope set to a slow timebase and the trigger accurately set - not too hard to do.
But why all this high tech stuff? It is easier to multiply or divide a known frequency from a sig-gen by 60.
Robert
