Automating a legacy home alarm system

I have an old legacy home alarm system. It’s reliable and uses our landline (Vonage) when the alarm is tripped.

We arm it using a keyfob, similar to arming and disarming a car alarm.

However, it’s not automated and it’s not connected.

I wanted to connect it to the net so I could control it remotely, and I wanted to automate it using IFTTT and SmartThings.

I ended up using a Particle Photon and a Relay Shield to get this project completed.

Here’s the full writeup:

Here’s a short video:


Fantastic job.
Can you point me to the exact relay model?
Can see a few options in their website.

Are you aware of any limitation of using specific fob keys?

1 Like

Hi @Sergio_Ferreira,

Thanks so much, I set this up in Feb of this year (2016) and it’s still working perfectly.

I haven’t had to change anything, or touch it since I first set it up.

This is the relay I used:
Relay Shield for Particle Photon I²C 2-Channel SPDT 1-Amp Signal Relay with WiFi and USB Interface + 6 Programmable GPIO

As far as the FOB key, as long as it has exposed terminals, you can experiment with a wire by closing the circuit to simulate a button press.

Once you figure out which terminals to use, it’s easy. If the FOB doesn’t expose the terminals, then this solution won’t work for you.

Also, the FOB that I have had separate arm and disarm circuits, so that made it easy to ensure I was actually arming or disarming. Some FOBs may only have a single button to do both functions.

Good luck, I hope this helps and you are able to create what you need.

thanks for the detailed reply.
Was it required a Particle Photon on top?

The Photon is what gives you the WiFi (Internet) connection, which gives you access to IFTTT so you can control it through a SmartThings IFTTT trigger.

1 Like

Interesting. I have an old system in my home that built in 1997. Seems to work ok, but no FOB, wonder if there is a different way to connect directly to the panel.

I’d love to automate using existing hardware. I’ve looked into replacing the panel with a newer web capable one. Panels are relatively cheap, but the keypads are pretty expensive, especially since I would need 3 to replace all the current keypads.

1 Like