Eric, you are right for the location: done!
The solution that I’m looking for regards an improvement for some controls in the train plastic of a friend of mine.
The Vin = 0-5V comes from a position sensor ( I think a potentiometer).
Eric, your suggestion is a VCO + band pass filter, …correct?
Optikon, may you explain better your proposal?
Thanks to all of you……something of good is coming out!
PS
I added a new img reviewed (I hope more clear than the previous)