Hi Robert! Back after a 10km fast walk by the sea and had time to experiment a bit. I first tried putting the ‘scope into DC coupled mode as you suggested and the pulses do look nicer, although still only 20ms duration:
So I tried a 0.47uF cap across signal to ground to try and extend the pulse a bit:
Works slightly but not enough, then a 10uF:
Works and pulses get counted OK! But that stretches the pulses to almost 100mS so maybe a bit much, depending where the cut off is.
Finally tried 4.7uF as a compromise - still counts OK but about half the time constant. So I’ve left that in place and will do a longer term comparison between the meter reading and the Emoncms system.
Thanks again for your help. Without your knowledge that the pulse length needed to be >20mS I would not have succeeded! The capacitor solution is not as elegant as a software solution but it’s quick (and dirty!)
