Hey Team, I know there are a few threads bout perimeter security, but wanted to revisit the subject with any new ideas/items you have.  I've been using a cheapo audible "purse" alarm, with kevlar wire, and I'm not sure I like the primer alarms, either .22 or 12ga.  I like the idea of a constant alarm.  If i'm asleep, and one goes off (assuming you have multiple set up), I may not know exactly what direction the perimeter was breeched.  

So, any hints, tips, new products you have would be appreciated.

I was experimenting with making my own 3d printed perimeter alarms that fire a 209 primer.  It takes an insane amount of spring force to pop those though, which stalled my experiments.

Seen an IR becon trip flare which was pretty bad ass. Clearly that's a special use device that would require active monitoring....at night......with NVGs.

https://gmstactical.com/phoenix-jr-intruder-beacon-trip-wire-system/


Special use device when you are expecting contact.

Same as you I have two of the small electronic alarms and a roll of wire and a roll of fishing line (one of those tiny "starter" spools you can find in Walmart).  I bought the white versions and painted them OD.  I had a second set, just bought them black, made by a different company that had a different sound but I had been carrying them overseas and think I left them there.  The original ones are GE branded and after testing them I put the piece of plastic back over the battery and they were still good last time I checked them.  

I've looked at several versions you can 3D print and if I ever get a printer I figured I'd make a few of the ones that use the .22 powder charges- you could still find powder actuated tool loads when you couldn't find 209 primers.  I've made a couple different types including the mousetrap and pipe with a spring, primer and washer types but the electronic ones- good to know I guess since if it goes off there's a good chance you won't be retrieving it, but the electronic ones don't look as suspicious if you get checked (I carried the factory black ones on trips and never had any questions even when I had one in my carry on; good for slipping in your bag and safety pinning the pull part to your clothes when you're sleeping in an airport, use in a hotel, etc.

I have been using the Yolink system for various home automation, and they have some interesting motion sensors.

The Amazon thread also had these driveway alarms for $25 recently, haven't tried them myself

These ones got decent reviews and are loud as fuck!
Intruders will be deaf.

Dakota Alert MURS alarms (IR motion detectors and magnetometers for detecting vehicles) can be programmed to multiple zones.

You just flip a switch on the transmitter part and it will switch from "Alert Zone 1, Alert zone 1, alert..." to "Alert Zone 2, Alert zone 2..."

You can program them for zones 1 through 4 but you can also program the number of times it repeats the alert (up to 5 times I think) so if you awake on the first one and count the number of times it repeats that breaks it down to 4 zones with 5 different sub-zones, or 20 different alarms that will send out individual, unique alert messages. And it's totally wireless and the signal can be received on hand-held radios. You can program Baofeng handheld ham radios to receive-only on MURS frequencies.

I also got something similar. These had pretty impressive range I will say:

https://www.amazon.com/dp/B08GCHNDSS?tag=arfcom00-20

Nice thing about these is they probably will not know they tripped the alarm.

I'd like to get some of the 209 primer grenade fuse trip alarms....a couple years ago I looked at them and guys were selling 6pks of them....now I can't find anyone selling multi packs.....anyone know anyone that has them? Thanks
I'd buy a couple of the 130db electronic alarms if I can't find anything else...

anybody here have any experience on using the MURS driveway alarms under canopy works?  I would think the wind blowing through vegetation would cause a lot of false alarms.

I'll have to pull out my "portable alarm kit"

So, the ones I like the most are the smaller ones that fire off the 209 primers. For a portable system, they're pretty decent and pretty robust. I think my alarm kit has four or five devices, cord, a couple of nails/screws and extra primers.  

I also have the shotgun devices and a couple bags of blank shells. They work quite well, but they're bulky. If I was doing security for a vehicle-base camp, I would likely go with these.

For an easy travel (including air) kit, I have several of those pull-activated rape alarms; they're loud as shit. I kind of like these for SHTF because if you need to grab shit and go quick, you're not out much. They're pretty light as well, so carrying four or five isn't too bad if you need an early warning system.  

Oh, I've got a bag of grenade ignition devices, but I need to get them drilled properly for primers. They're a cheap option.

Practice with them. I like the primer-fired devices, but you need to learn how to set them correctly, understand the necessary tension (pull/release), and where to set them. I actually like finding a hide or camp site where I can limit egress to three areas. It just makes it easier and while you could square off and get a complete perimeter, likely avenues of approach can help maximize just two or three.

I need to eventually get the MURS one set up for my driveway entrance...

ROCK6

One of the problems I see with the primer or shotgun blank alarms is they are one and done. If you have multiple set up as a perimeter it makes it more difficult to know exactly which one was triggered and where the intruder is. With the "rape" alarms they continue to go off which helps to pinpoint the area. I'm not too sure how waterproof those alarms are so they may not work reliably in bad weather.

They have adjustable sensitivity; when I first got them I'd get false alarms from brush in the wind, but after dialing the sensitivity back it was fine and would still reliably alert to vehicles, humans, and dogs.

I like the battery operated pull-activated alarms. Cheap, loud, small and lightweight, and for portable/grab-and-go, buy a few different types on Amazon and use the ones with different specific sounds for N, S, E, and W,  and play with them a few times so you get accustomed to which sound is which, and whenever you set them up, use the same orientation.

Can cut down how many types you need by using the same type/sound for N & S, and a 2nd sound for E & W, as it should be readily apparent whether it's N vs S,  or E vs W etc.

For a permanent installation with constant monitoring, I use a combination of break beam and passive IR motion sensors.  With some adjustment, I have almost zero false alarms.

Passive alarms work best when aimed at a solid surface like a wall or fence.  They are prone to many false alarms if pointed out to an open area.  The break beam works great when a person or vehicle crosses my front property line.  The only time it has a false alarm is during extremely heavy rain or fog.  Very rare.

So, is the Dakota MURS still the go to for long distance motion detection?

My old system finally gave up the ghost and and so I’m looking for a couple motion detectors and a vehicle sensor.

And does anyone know where to get them cheap?
I thought there was a member in the SF who had them (maybe Lowdown?) but I can’t seem to turn up any mention of them.

I considered setting something up, but unfortunately I think it would primarily be set off by animals.

As of now I just have solar motion lights, and they are constantly getting tripped with nothing there. If I'm not watching, I don't know. I do have Blink cameras set up also, but same issue. They go off so much because of wind, bugs, birds, etc, that it becomes an annoyance and a waste of battery so they get silenced.

One day l, I'd like to own a compound and hardwire IR motion lights all over the property. I'd also like a solid set of NODS to watch it with..... One day.

I geeked out and made a few kits that use grenade ignitor's and shotgun primers. Prices seem to have gone up some. Search permiter alarms on ebay. No affilication

https://www.ebay.com/itm/266156269553?hash=item3df8265ff1:g:ydwAAOSwoiJkAX8W&amdata=enc%3AAQAHAAAAoAKhmpb73H06npj1CvgZjNsYFCEbu3wje3pm506ylIhZoa09LJpVjqIZNZ2pf%2Be%2B5umuoDsUYXwpqNgMWDeOcNlMD2BagUARi%2FN4HCFxO8uud0HcSbFGCusEWXB%2Fo8kis6Yr9nZHjzVXh44IayqnPfHSMm8MubggbZNbdsS7kwQdQU7N%2B7MGqramJUmwQ4ZgC1YAqwf1aNE3sVvI9Pn2fHg%3D%7Ctkp%3ABk9SR6qo8YbVYQ

It's Lowdown, he price matched a competitor and took good care of me.

How remote would this be?

Why would a dog(s) not be good for the area?

Especially if this is a wooded area anything could set it off from a deer to a branch

I have been testing 3 different solar motion-detecting lights for installation around the farm...  It occurred to me that they could be a cheap mobile visual alarm in any location, which could be converted to audio with some work.

I want to also point out how the MURS alarms work because I think it is quite versatile for alarm/alert purposes.

Internally the circuit board is split into 2 different parts. The sensing portion is always powered and is passively watching for the signal value to cause it to trigger. The radio portion is a separate circuit board that is connected by wires into a terminal block. The radio board will immediately begin broadcasting the preset signal on repeat for as long as it is powered on. The sensing board just puts power to the radio board for a preset amount of time when it triggers. You can utilize those 2 power terminals (12VDC IIRC) to power anything you want. Just be aware of the power requirements of the thing you're powering, you may need an auxiliary battery and a relay to power things that would draw more than the the few watts the radio board draws.

With that the sky is the limit. If you want an IR beacon to illuminate and stay illuminated until reset you just need an auxiliary battery, a latching relay, and the beacon, and boom, once one triggers, it lights the IR beacon. But wait, what if you want the MURS radio Alert to play as normal AND you want a loud siren to play for a set time in addition to the permanently lit IR beacon? Leave the radio board hooked up, hooked the beacon to a latching relay, and the siren to a time-off relay. You just took an off the shelf sensor and made it do multiple functions with a few very basic off the shelf components and a little knowledge...you don't have to build the sensor from scratch, or know much about circuits, the circuits don't get touched other than knowing not to draw too much power from them and tapping a signal off they aren't changed.

With a 3D printer, you could probably design a wind up siren/alarm that plays different continuous sounds. That would let you have different sounds set up in different areas that tell you more information about exactly which alarm got tripped.

You could also make a good chemstick breaking mechanism.

A mousetrap will break a chemstick, but you need to mod them a bit to make them harder to spring or they trip too easily.  There are several versions of the 209/powder actuated alarms on the 3D printer sites.  If you wanted some simple noise makers I'd go to some of the local Goodwill type places, buy the annoying toys that parents dropped off (Hess trucks, fire trucks, even some of those animated pets that make noises, etc- heck, some of those talking dolls could creep someone out) and just pull the sound boards out of them.

I’ve been experimenting with the primer type alarms that are very robust and would be ok in wet weather. In my case if I’m sleeping alone and one pops off it would take me a minute to get orientated.

The pull alarms are more of my liking but they are not waterproof. I tried the paint in rubber cement stuff and it didn’t satisfy me on the waterproof ability.  The other big positive to these alarms is having a strobing light along with the noise.

All in all these are a whole lot lighter and less bulky to the old school permitter trip flares.  Plus not a very attainable item on the civilian side.

When I've used mine when it's raining I just put the small ziploc I carried them in over it.  You could easily make some sort of cover out of something moldable like Kydex or even just glue a small pouch out of some waterproof material like an old drybag or something.  

Rain, and being cheap, are actually a couple of the reasons I like the idea of 3D printing something that uses those powder actuated cartridges.   I really don't care if it only last one shot, if it goes off you're probably not going to have time to retrieve it and you could make it small and light enough to carry a handful of them.  I doubt it'd be difficult to incorporate some sort of cheap led or chemlight if you wanted to.  The led could be as simple as a clothespin style connector while the chemlight just needs a spring to snap it.  Jmho

I have the 209 primer fith ops perimeter alarms they are well made and work well.

www.fithops.com

Excellent suggestion. Thank you.

I made 6 of the 209 trip wire primer alarms. On the subject, do you set the trip wire low or high? I envisioned it being about 8 inches off the ground, but even small critters could set it off.

I was always told to take ground cover and location into consideration but about six inches to a foot above ground level will snag them even if the critter is raising its feet as it walks.  The lower it is, the harder it is to see but you don't want smaller things and blowing vegetation tripping it either, unless you're trapping small critters that is.  Definitely not my area of expertise, just what I've heard from folks who were considered experts.  

One discussion on making and setting them.

That's interesting. I welded two small chain links on the back at 45 degrees for securing them to a tree or a stake. He is correct about putting together a kit with tie wraps, trip wire, and 209 primers. I'll be working on that. I tested them in a vise after putting them together. A guy came in and said what are working on? I said listen to this and pulled the wire. It's pretty loud in a room. Mine are bored almost through with the gas exit holes at 90 degrees. You can't use them as something to injure people.

Chamberlain motion sensors.

I was in Walmart last week and I looked for the personal protection alarms or whatever they call them and they don't seem to carry them anymore; I haven't been in a Target in years and not sure where else to look other than Amazon.  This might actually be something Wish/Temu, etc is good for.  I want cheap since if I'm in a situation where I need something like this (outside of the ones I carry traveling), it's probably a single use item ('cause if it goes off and I've done my homework, I'm grabbing my gear and egressing as quickly and safely as possible).  

I really need to learn how to 3D print (and buy a printer).

ETA- Temu sells them for about $6/shipped with a strobe function; DHGate has some cheaper ones without the strobe.  Guessing I need to get a prepaid credit card.

Looks like Harbor Freight sells some window alarms, including vibration models, that might work too.  Something like this six pack would be handy, especially with the remote.  Too bad it looks like they're discontinued and it doesn't show which stores may have them. https://www.harborfreight.com/six-sensor-wireless-home-alarm-94799.html