I have made a modification,i replaced the simple telephone cable anemometer La-crosse,with a shield CAT 5 FTP cable ,because some times La-crosse modells ws-23XX if there are electromagnetic interferences near them,show false air speed readings 91,8 km/h.
For better results i have added 2 ferrites and the two end of the cable ,one ferrite near to anemometer and the other one near to RJ 11 connector.