[werk_ag]

... That might be the way to do two sensors for the anemometer, provided that the "inactive" magnetic state gives a High output level (otherwise you need an AND gate).

Hi AllyCat

To avoid such "complications", I'm testing a modified FO anemometer with just one hall effect sensor, which gives me only one pulse per revolution. Since some weeks, I'm testing it side by side with a standard FO anemometer. The gust readings are very very identical, and the average speed readings are exactly the same.

To read both anemometers I'm using two WeatherDuino Pro TX units, one of them with a slight change on the software to adapt to one pulse per revolution instead of two.

Modify a FO wind vane to use hall effect sensors instead of the reed switch seems to me complicated, and maybe not worth.