RF Two-way alarm

Hi Everyone,

I'm new to the forum and fairly new to the Arduino IDE.

I would like to create/setup two RF communicating, battery operated (will use rechargeable batteries) arduino nano's where a two way alarm could be triggered from either of the two nano's.

We already have a standard panic button installed by the security company but after we and our neighbours decided, we would like to install our own "private" alarms in case of an emergency.

Can anyone give me a point of departure? Best equipment for this?

Thanks

Do you want this to be triggered by the button installed by the security company, or a separate button?
What is the distance to your neighbour?

Conceptually you need the two devices to constantly send messages to each other with a status bit indicating the alarm status. You can trigger on a change in the status bit, or the loss of communication.

For the RF part: find the requirements for link you want to create (bidirectional communication, required distance and operating environment). What unit to use depends on this.

Also think of what you want from the alarm device. What form(s) of input, what form(s) of output.

When you decide on those things and have proper specifications, it's time to think of specific pieces of hardware.

The problem with wireless communication is the things that get in the way of the wireless signal - like walls and trees. And the longer the distance the more that stuff matters.

Without having that information any advice would just be guesswork.

...R