wireless ir activated security light

Thread Starter


Joined Sep 16, 2016
Let me start out by saying im new to building circuts. I have done a little bit so far but im struggling on this simple project. Any help would be greatly appreciated

Im trying to build basically a wireless setup to activate a relay so that i can run aditional ir flood lights on my property. I have security cameras set up but the light they give off is poor and would like to run another 1 to help boost the covered area. I was hoping to trigger the second light by using a ir sensor off the lights on the camera. The second light will be run off of a 12v battery and solar panel. It will need to include an adjustable timer so that i can vary the length of time the light is on.


blocco a spirale

Joined Jun 18, 2008
Aren't the IR lights on the cameras simply activated when it gets dark? In which case, don't you just need the second light to do the same?

Alternatively, control the second light with a 12V day/night PIR switch to minimise the drain on the battery.
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Joined Feb 5, 2010
If you have a motion sensor that activates a light, what exactly is stopping you from activating the second light via that same sensor???

Thread Starter


Joined Sep 16, 2016
unfortunately the sensor is inbuilt into the camera. It would require breaking open the waterproof housing. That's why I'm hoping to just be able to mount something infront of the ir leds on the camera to trigger the second 1 to turn on.


Joined Aug 1, 2013
An IR phototransistor should do it for the sensor, followed by a comparator (maybe as simple as one more transistor), and a relay driver. All of this needs some kind of power source. 5 V, 12 V, whatever.