The bluetooth disruption

Well... As I needed some lighting at "Lantern Garden" I bought two 12 V/10W LED projectors and assembled them in the rural field, though I had a problem, where do I put the light switch? And what about rain? It will be ruined very soon... And humidity in the area is quite heavy, so I decided another way, but it needed planing and more hard-work!
At left you can see the light pole and water-resistant distribution box with the projectors assembled (they already have some corrosion because of humidity...).
My decision was to use a bluetooth device I bought for quite sometime now, and to increase the area covered by the signal I put a small waterproof box about 20 meters from the main box, as I need to light up outside the area and not inside it, otherwise I would enter the field without light.
The picture on the right has the bluetooth device already connected and about to be closed inside his "home". For getting it to work I assembled an arduino (wich gave me a huge headache with the resonators I bought, they simply didn't work!) which interprets the bluetooth signals and transfers it to digital/analog pins, at the moment it only lights the projectors, but.. the sky is the limit!
To drive the 12V/10W LEDs I used a TIP120, and it works fine as you can see on the picture on the right and the bluetooth signal gets quite far, I'd say.