> The Detroit Police Department no longer responds routinely to house alarms, because 98% of house alarms are false. Detroit Police officers will respond ONLY to house alarms that can be VERIFIED as not being false alarms ... DPD recognizes four different ways that an alarm can be automatically verified ... An alarm system sends one signal from a door, window, or other perimeter/exterior sensor AND sends one signal from some sensor inside a house. An alarm system sends three signals from one or more interior sensors. An alarm system sends an audio signal that lets a company monitor hear an intruder. An alarm system sends a visual signal that lets a company monitor see an intruder.
> Do sound alarms deter only small burglars?
What deters non-small (organized?) burglars?
I think organized criminals would call off an operation if circumstances they haven’t predicted occur. Especially those that significantly increase the time or reduce the chances the operation will be successful.
One thing is having the inside doors lock. Another is encountering an armed individual. Finding non-portable hard to open safes, etc.
But then again, it’s mostly better to diversify where you keep your belongings so you don’t end up a victim of organized crime in the first place.
40mm noob tube auto turrets and lava pits.
The best deterrent is quick reaction, even unarmed civilians with torches and calling each other on mobile phones.
The system should rarely/never generate false alarms (crying wolf). Outdoor sensors should only be used if they are completely immune to pets and weather.
Security cameras is mostly used for post mortem. For reliability, it's better not integrate them with the alarm system.
But then again, one could have a short lasting warning siren, and then a full blast one when someone does break in.
Should we set off the alarm by accident, we then have 20 seconds to fix it, before all the neighbors are alerted.
Right now I’m thinking about simply processing the outdoor cameras rtsp stream for people detection and then triggering is if it has a certain confidence.
Can be done quickly on the Pi with something like a google coral accelerator USB stick.
You can also have it send the photo it detects to your phone and you can manually turn on the alarm with that alert after viewing it.
1. Hm, maybe. If they were to arrive, they would have to call me — I could remotely disarm the system or give them the code.
2. Not sure, my closest neighbors are aware of the alarm system. No false alarms in 13 months I've been using the system.
3. I used to work as an alarm technician; you can't really prevent the pros breaking in, getting what they came for and getting out. But you can prevent someone spending a long time inside the house looking for things to steal.
That’s great. How often do you test it?
> I used to work as an alarm technician
Ok, that explains a lot.
> you can't really prevent the pros breaking in, getting what they came for and getting out. But you can prevent someone spending a long time inside the house looking for things to steal.
That’s the main use-case for such an alarm then.
We chose a ‘dumb’ old school wired alarm because they run reliably for years with just battery changes and dust blow-outs, and linked it to a network dome camera to handle the ‘smarts’.
Most sensors gets used on a daily basis — as they are part of other home automation, like motion activated lighting. I can put the system in "walk test" mode, which gives a verification sound every time a sensor is activated. And there is a siren test function. I try to do those about once a month.
> That’s the main use-case for such an alarm then.
I'd say so. As I said; we have good neighbors that would react to the alarm, and I get notified on my phone. But the pros are normally gone before anyone has time to react anyways :)
Having my house visited once while I was away and twice at night when I was there, I'm now prepared. The two times I was there, I make the bad guys run away but I still don't know if they knew I was there or not and what their plan was.
So now I take no risk and I've got an amazing alarm system.
To me the most important is that the alarm makes it physically impossible for the thieves to steal much. My alarm system gives the thieves 45 seconds to give a password (and they don't know it). If I'm under duress, there's a "I'm under duress" password and the security company will answer: "Fine, have a good night" while they actually call the police. So the thieves cannot know.
If no password is given, after 45 seconds a smoke fills the entire house. It already triggered, worked wonders. It leaves no trace once it dissipates.
With the smoke the thieves cannot steal anything. They certainly don't have the time to find the safe / open it.
The game becomes: "Without seeing anything (due to the smoke), find the door to flee the house before the police arrives".
That's what I love with this alarm system: it turns the thieves into preys.
It's communicating over several channels (as an anti-jamming system). It's got its own battery.
It also detect break-ins attempts, before the thieves are even in: the sensors detect the vibrations and it works (one day I let my hammer drop and that was sufficient to trigger one of the sensor).
They can still break a lot of things while they try to find the exit ...
I don't know about Norway, but just south of Norway, in Denmark, having something automatically call the police would be an issue. Not sure it's illegal, but there are rather few police officers in many parts of the country. In the northern part of the country you have a large zone with zero police officers on duty for the entire winter and similar situation elsewere in the country.
The author may very well have good reasons to dislike the security companies operating in Norway, but the service they provide isn't actually the alarm system, it's the operation center staff and their security patrols.
Without the security service, I'm not sure I see much value in an alarm system.
Reading this post I was coming up with so many questions.
1. Shouldn’t there be a way for police to turn it off?
2. What are the legal consequences of the alarm accidentally firing and disturbing the neighbors at night?
3. Do sound alarms deter only small burglars?