Certainly has a lot of potential. I like the fonts. Instead of having an O in SOS, maybe replace it with your lifesaver art and add two more red circular bars to it so that it is easier to see that this is a telecommunication device. Instead of a black background like #5 create a square with rounded edges, like a button. If it wont be too busy add a light gray shadow figure of a man (in a hat and overcoat) lurking in the background under a lamp post.
#18 new version that might make more clear the signal (and the life saver). Another designer is using it as the O in SOS so I can't use it (I will ask him though). I will be working on other versions as the contest goes. Thanks