This is my Stevenson screen box,we can make a Stevenson screen box.The size it is 30 cm x 30 cm x 47 cm high,
Here i have photos how i make it.I have it 2 meters above the ground.
Insulated material has been placed on/under the roof in order to prevent high temperatures inside
The 2m high wood construction
...and finally it is 2 meters above the ground
A plastic tube with a fan, helps cooling the inside (I put it above the temp-humidity sensor, like a hat)
The fan power source(12V/1A), with 1A glass fuse and on/off switcher with remote
The down side, with a small 12V green light, to watch the fan on/off state from outside