So having discovered the first unit would not connect to the smart app and thence to Google, I ordered another (which was cheaper) on Friday
Identical casing, but no battery or solar panel. This needs a permanent
12V PSU.
Have no idea how I got it into pairing mode - a series of pressing the "set" button. The LED blinks red, not blue. But it paired immediately and showed up in my Tuya Smart app, and thence Google Home.
After some limits fiddling, it works *almost* fine. The only snag being that Google seems to think it's reversed. So to open them it's "Hey Google, close the curtains".
I shall fix this by reversing the cords and not telling Google :)
But for <£40 (when some places will happily sell the same solution for £120) seems a win for d-i-y. And now SWMBO can work these curtains (since she can't get close enough to pull the cords).
These curtains are on the east side of the property. Which means when they are open on a bright day the sunlight does a damn good job of warming the room and thence the house.
I find myself wondering if opening them at sunrise could save 'leccy ?