Well - I just got a rather rude wake up call - at 1:30am my phone got triggered by a Civil Defense emergency test with a standard emergency tone (sounds like This) followed by my phone reading out the message out loud with no way of shutting it up:

And, just as I was falling asleep another one came through at 1:50am. Hearing that tone sends chills down your body especially when it is played loudly on a phone right beside you...

I heard they were planning this but didn't think they actually implemented a system yet but anyway - thanks Civil Defense as I am wide awake now, your system works.