New to the community and less than a hobbyist so please advise if this question should go elsewhere.
I am not noting a particular alarm clock or model because I would like this to be repeatable across any/most generic store-bought types of digital alarm clock.
What I'd like is to have the user set the alarm clock as they normally would and when it 'rings' I need some form of an output. This should be either some sort of voltage (nothing high or high amp, 5 or 12v and 100 or 200ma should be plenty) or perhaps just a contact closure.
This would then be taken to a home control system to perform whatever tasks are wanted for wake up and so that is why the question is in generic terms.
Can this be achieved in a way that can be generically applied to most alarm clocks and if so how? (in somewhat noobish terms if possible)
Best Answer
If you can tolerate having the buzzer/speaker still sound when the alarm goes off, then you could attach a microphone to the side of the case, and then you wouldn't have to open up the case at all.
Use a circuit something like the one below to convert the output of the microphone (fed into the Audio input line here) into a digital signal at the output of the comparator.
The circuit doesn't specify a comparator, but one you could look at is the LM311. It can sink 50 mA, which would make it ideal for driving a relay.