Chicken door opener

The door opener on the main chicken house broke late last year. It had happened a few times before but this time it was not fixable. So we bought a new one. The old one was inside the house with a sensor poking out. Good from the point of view of being sheltered from the weather but it meant the chickens were always knocking the string off the door. This one fits to the outside of the house and has the sensor built in to it's body. Much better, but we have not fitted if for ages because we couldn't work out how to get it to raise the door which was inside when it was outside.
I suddenly had inspiration on my long drive from Toulouse on Thursday and realised we could move the door to the outside!
This is the chickens view from their house. Well a bit above their house. Aren't they lucky!

New opener in place