A lot of us have an intercoms to let our friends and service workers into the building. I want to modify mine so that every time someone rings my buzzer I can get a notification on my phone and if I choose to, buzz them in.
Here is the pdf schematic of my device (4-wire setup).
Here is the actual photos of the circuit:
I want this first meetup to just talk about what actually needs to be done? How does one capture the signal from the device and how can you send the signal back to the device? Once you capture the signal, how can I get it on my phone? And lastly once the phone receives the notification, sending one back.
This is scheduled for variety cafe but if it is too crowded I'll just move the event to the bar down the street.