I've been looking long time for something like this. :-) It is very simple to use and works as advertised. Only one serious bug: it notifies with sound even when the phone is in silent or vibrate mode! 73!
v1.0.1: 7 dit pause following alarm prefix
v1.0.2: Audio tone and usage as plugin for Locale, Tasker, Llama etc.
The first and only app allowing WSPR transmission using your Android device!