Anti Porch Pirate Alarm

[billbyrd1945]

I tried a cheap Amazon PIR motion detector which proved to be useless as I expected. Sent it back. I have my mind made up that garage door sensors would be the way to go as they seem very reliable in their intended application.

I have a rough idea how they work but I could be wrong and I'm not sure how to proceed anyhow. Here's what I am thinking: the 2 sensors with 3D printed holders; a doorbell mounted over my front door (inside) with a 120v transformer and a relay; an Arduino to provide the signal to the transmitting sensor. Is that possible?

I'm pretty sure the signal must be PWM. But I don't know what duty cycle, or how to put it all together or how to write the sketch. I do have Arduino Unos from a few years ago when I was working really hard to learn about them.

I can certainly bone up on PWM and sketch writing. But I do need some guidance. Any help would be appreciated. The doorbell sounding would alert us to porch pirates and, as a bonus, would let us know that UPS just left a package on the porch in the rain. Thank you for reading my post.

[mosafet]

You might look in to RF/microwave/electric field sensing devices. They can sense bodies at a distance. These used to be used in car alarms until they got so annoying that nobody wanted them. Of course the most widely used devices are the infrared motion sensors used in automatic lights and such but you said that didn't work, maybe you got a bad one.

Personally I just use cameras w/ motion sensing. There are cheap cameras with full wifi and such and open-source Linux running on them (eg. Wyzecam cameras; dafang firmware). Not much effort needed to make these work and you can program them to do just about anything. The built-in/hardware motion detection in a lot of these is not very good though so external processing may be needed for really accurate results.

[rstofer]

As an alternative, you might look at this driveway sensor to spot people and delivery vans entering your property.    We have one and it works quite well.

https://www.guardlinesecurity.com/products/guardline-500-ft-wireless-driveway-alarm

The batteries last a while and the sensor is mounted to a tree off to the side of the driveway.

The receiver works on mains and battery.  When on battery, it can be brought outside to help with aiming the sensor.

[billbyrd1945]

Decided to take your advice. Went to their site and found them on sale from 149 to 99. Went to Amazon and found it on sale for 49. Thank you.

[Gregg]

For few if any false alarms, look into the dual beam infrared systems for alarms.  Optex, Takex, Wonderex are some of the brands.  ebay item 115084948416 is an example.  A little research will differentiate all of the different models and features.  They do require to be mounted on both sides of an area so that both beams will be broken by someone or something.  They are very reliable and rugged.

[Psi]

You might also try a sign nearby where your packages get dropped off that says
"If you can read this sign we already have your face on HD camera, don't even try it."