The question if using cheap ebay acoustic distance meter modules _can_ be used to do wind speed and direction measurements needed to be answered. In a first test the pulse changes were too small to see with 50 Hz repetition frequency using my finger and mains frequency as trigger.
Well, if all else fails use differential mode. So I used 2 of these distance sensors, removed the TX side piezo, (remember that one on the MAX232), and put them apart facing in opposite directions.
Then took the good old 74HCT86 XOR gate, to see the difference (differential remember) in pulse length between forward direction (wind) and opposite direction (wind).
This is without wind, on the good 'ol analog scope:
And this is with wind made by a PC fan on 11.4 V:
So from this follows that by using 4 cheap ebay distance sensors
Anyways, you all know those sjips, xor, PLL, so no need to draw the circuit diagram . Just follow the grey wires in the pictjures... :-)
My tronics for today, need coffee. do not gimme that 555 jive, yes that would work too, but I have none, I stocked up on loads of 4046, it is still the most universal sjip I have come across. Yes maybe you could use the xor in it, saves a sjip, that was actually the original plan, but forgot about it, wanted only to see the diff, but then still needed more trigger speed, so had to wire it in anyways.