[werk_ag]

I think that I have worked out the pins for the wind connection terminal on the TX board :

1 = 12v
2 = gnd
3 = gnd
4 = D3
5 = A3
6 = 5v

Hi tyntop

The pinout of the wind connector is correct. You may not even need any connection board, if you manage to connect the wires from both the wind speed and wind vane sensors to a single RJ12 connector.
There is no need to use any extra capacitors or resistors.
You can supply power to both sensors from the 5V pin, and connect the wire with pulse data from the wind speed to pin 4 and the wire from the variable resistor of the wind vane to pin 5 of the RJ12 connector. GND is common.
If you have previously used the TX board with an FO wind vane, don't forget to remove the jumper on the TX board.