Let me lay the cards on the table: I am coming back to sensor construction after a five year hiatus (I’m a geology/env sci prof and covid sort of wiped out cool things like this for me). So I’m trying to spin back up and I’m hoping to implement a water level sensor in our university’s water sumps to monitor ‘invisible’ water as it flows through campus. This is part of a course. My intent is to install 4-5″ PVC stilling wells in the sumps, then mount the ultrasonic probe to a pvc cap, as you show in your post (https://www.envirodiy.org/ultrasonic-water-depth-sensor/). Because this is an indoor deployment I can use local power supplies and the university wireless to transmit data from the sensor/mayfly and that is my plan. When I look at the Maxbotix specs the MB7375 (RS232) or the MB7395 (TTL) with the larger cone seem the most appropriate because of the 1.5 m range. My first thought was that I would use TTL for serial communication, but I don’t have a strong reason to prefer it because it seems like both TTL and RS232 would work. That is unless the beefier RS232 power pulses would somehow be better for communicating with a wifi card, but that seems unlikely to me (as you can see, I’m no electrical engineer). So, given that you, Shannon, seem to be the guru on these sensors, any help you can give would be very much appreciated. I learn well from looking through existing code, so that would be most helpful. If you have a strong preference for a specific wifi board, I would appreciate your recommendations as well. I’ve looked through the modular sensors site on Github and there seem to be a plethora. My colleague, Beth Fisher, used SIM800H Wireless cellular boards for a project we did in 2018 and I still have some of those, but I’m not interested in cellular comms for this project.