arduino mega2560 problems in sensor's output

Hello!
i have connected a dust sensor to arduino mega…(i copied the project in this great page)
the sensor works correctly and indicates pm10 and pm2.5 values on a lcd shield…
the fact is that i want to send the data in real time to Thingspeak by an Nodemcu module…
connecting directly the sensor to the module gives me back nonsense data…so i would like to use the connections between mega and the sensor to send, by the nodemcu module, data on the net…
is this possible?
thanks for any help!
stefano