I soldered the Schmitt trigger onto a BoB then bodged it onto the HMI board using 0.3mm bodge wire. The controller is an ESP32 and I was having trouble with the hardware interrupts because the RC debounce I was using was too slow. The Schmitt trigger gives me a nice, square signal which the controller interprets properly. The chip cost me a couple of bucks from Digikey.

Here’s the best RC trace I could get.

and here’s the trace with the Schmitt trigger (same scope settings.)