Thank you Chris for the instruction. I'll use this to set up my single zone. I've noted your valid cautions.
I'm going to purchase and install a Rain Bird SMRT-Y Soil Moisture Sensor Kit for the zone removed from Rachio G2 autoscheduling.
It's easy to see that the Rachio G2, theoretically, is trying to model the same results as a moisture sensor would produce. All in s/w taking into account a bazillion factors.
I want to see where sprinkler control via soil moisture measuring technology is at today. I want to see if a h/w solution is ready for 'prime time' yet.
My detailed question include:
1. Can I use it to turn off the zone once enough water is applied, or, will the zone's moisture level over shoot badly?
2. Will it turn on reliably when soil moisture gets low?
3. How will rain affect the zone's operation?
4. Will the zone use less, same or more than a Rachio G2 auto-everything-on zone use?
5. How long will the sensor last in the soil?