I recently began trying to implement pulse counting of some so called smart electricity meter.
Starting off with a TEKT5400 phototransistor i failed, even after some different attempts.
My main problem seems to be, that I am not able to measure the minimal changes, if there are any.
At the moment i’m leaning more towards a low tech solution misusing an analog sensor into functioning a bit more like its digital counterpart. But if that will work out still remains to be seen.
Another alternative would be to simply get another phototransistor, and perhaps borrow a simple oscilloscope.