Ok Kai, I'll tell you what I was thinking when suggested that TIP:

I agree it's very simple to check the current value, but to check the waveform you need a scope, and many people don't have this equipment at home, and even if Eugene had one, I know it would be a VERY GOOD IDEA to know what the current is, but what i'm trying to say is: is it really necessary?

How about if we can design a circuit that doesn't depends on the current? That's what I was thinking when posted that circuit.

It's a general purpose circuit, that should work for any current a bit higher than 1uA, as Erik proposed, and lower than 5A.

When I said: guessing the current is below 5A..., I was trying to say: this is not a guess, it can't be higher than this... I just didn't see this as a guess. So, I am sorry if you and Erik understood it that way, but I was not trying to guess!

As you and everyone else, I am really not willing to fight thru an endless number of confusing posts, in fact I was trying to do the opposite: As Eugene's experiments didn't make a big sense, maybe we could come up with a circuit that doesn't depends on these experiments or values.

So, please accept my apologise, you, Erik and all the others who are trying to help.

Leonardo.