how to make a water level gauge with an ultrasonic and arduino sensor ?
Hi, this would be a much better question for an Arduino forum. Once you have it working you can feed the data into Node-RED.
Have a look at this 'post' on the ESP Easy forum.
Cheers from David.
Hi @unknow - here's a link to a tutorial that explains how to interface an SRF05 to a Wemos D1 Mini.
You could probably modify it to 'talk' to your Arduino.
One important thing to check is the voltage levels of your device with respect to the SRF05 (which has 5V logic). My write-up explains the various ways to handle this situation (if it applies to you).