Observation
As I mentioned earlier, direct observation of an intruder approaching is another form of detection, but I’m focusing on situations where you may not be able to have eyes everywhere 24×7. However, if an alarm does go off you’ll need some way to get ‘eyes on’ to determine what caused the alarm without unnecessarily exposing yourself to potential danger. There are a number of possible options to enhance your ability to observe a potential intruder.
The simplest and most obvious option would be magnified optics, such as binoculars or a monocular, assuming you have a line-of-sight to the area where the alarm was triggered. I’m not going to provide a detailed overview of optics, but you should at least understand how they’re rated. Most optics have two numbers – a magnification and a lens diameter, so a 10 x 36 device would magnify what you see 10 times, and the objective (front) lens is 36mm in diameter. Magnification means how close the image appears to be, so 10x means that something 100 feet away would appear to be 10 feet away. For the objective lens diameter, the larger the lens the more light it gathers, so larger lenses tend to provide clearer views and work better in low-light situations.
There are a ton of factors that impact the quality and usefulness of optics, but the two rules I try to follow are a) get the lowest level of magnification that’s appropriate for the distance you need to view, since higher magnifications tend to reduce your field of view, and b) get the largest diameter objective lens you can afford, consistent with other quality factors. There are a number of good articles on SurvivalBlog.com about various optics – take some time and do some research. You may also want to consider setting up an elevated position like a hunter’s treestand or a widow’s walk platform to increase your viewing distance. This ties back to the earlier discussion about mapping and planning your security system to understand your potential fields of view in relation to where you set up your sensors.
For observing really distant alarm points or for locations where you don’t have any line-of-sight, you may want to consider getting a camera drone. These are available in a wide variety of capabilities and costs, so do some research before investing in one. Note that most reasonably-priced commercial drones have a limited flight time, typically less than 30 minutes, so they really aren’t that useful for general patrolling, but they’re perfect for a quick check-out of the location where a sensor was tripped. Practice guiding the drone to your sensor locations to get a feel for what landmarks look like from the air and typical wind conditions. Drones tend to produce a unique and noticeable sound, so try to avoid hovering over one area where an intruder can take a shot at it before you can see them.Continue reading“Elements of a Security System – Part 5, by J.M.”