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twain
New Member
2 Posts |
 Posted - Dec 15 2008 : 7:52:26 PM
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I recently had a break-in at an outbuilding in my backyard, and many power tools, as well as other items were stolen. I live in the
country, and know that the thieves live nearby, although I can't
prove it; and even though the local PD agrees, they are too inept to
investigate and solve the crime.
The bottom line is: I would not be surprised if another attempt to
break-in is made at a later date. I have installed barriers, and
other defenses to make it harder to enter the building, but an axe
and a crow-bar (used last time) could eventually break through the
doors.
The building is wired with 110, and I have purchased a 127db horn,
which I plan to install (securely) which will go off if the doors are
tampered with, or broken open. I have no clue, however, how to wire
it, or where to purchase the items I need.
I plan on two contact switches on the doors, which, when separated,
will cause the horn to go off. I will need a 15 second delay, though, so I can enter and leave the building myself, and a separate
on/off switch, so that I can arm/disarm the system, while I am working in the building, with the doors open.
I know I need a 110V to 12V transformer, but I need help as how to wire the switches, and any other advise you could give.
Thanks in advance.
Twain
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audioguru
Nobel Prize Winner
Canada
4218 Posts |
Posted - Dec 15 2008 : 8:09:58 PM
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You live in the country.
You are thinking about installing a 127dB horn. Why?
A thief doesn't care if a horn makes a little noise in the middle of the country.
How much noise? 127dB at 10cm?
Then it is 121dB at 20cm and is only 85dB at 13m. Not loud. Just a little noise. |
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twain
New Member
2 Posts |
Posted - Dec 16 2008 : 6:26:14 PM
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audioguru
Thanks for the non-advice.
Even a fool should know that some people who live in the country have neighbors. There is a farmhouse across the road,
and those neighbors would be able to hear a horn at 127dB, even though they cannot see my back-yard.
Also, not all thieves are the same...I know these thieves, you don't.
You probably know how to wire the thing, but I don't.
Thanks again, for taking the time to to criticize, and not help. |
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pebe
Nobel Prize Winner
United Kingdom
1078 Posts |
Posted - Dec 18 2008 : 02:43:57 AM
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Perhaps you could use a low-power radio link to arm/disarm the circuit from outside the building. You would not then need the delay.
I am thinking of the remote controls used for closing garage doors, etc. |
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Aaron Cake
Administrator
Canada
6717 Posts |
Posted - Dec 18 2008 : 09:45:14 AM
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Honestly, I agree with audioguru. An alarm is of limited value no matter where you live. Even in the city, thieves will brazingly set off house alarms without regard because they know it's going to take at least a few minutes for someone to react. Someone a mile away isn't going to be able to react quickly enough to save you from loosing more stuff.
Head off to the local hunting supply store and purchase a bear trap. "Accidentally" leave it set just on the inside of the shed door. |
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Brian
Apprentice
USA
106 Posts |
Posted - Dec 20 2008 : 11:33:11 PM
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This discussion of the effectiveness of alarms reminds me of an interesting security setup that a friend of mine has. He has a light beam alarm and an inductance based alarm set up in his driveway. They are offset and create distinct sounds. They can tell if a car is coming or leaving. If only the light beam alarm is set off and they aren't expecting company on foot, they can grab their weapons and figure out what's going on before the person even reaches the house.
Luckily they live in a neighborhood where everyone is interested in discouraging any kind of intruder, so even if they are not home, a neighbor probably will respond. |
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audioguru
Nobel Prize Winner
Canada
4218 Posts |
Posted - Dec 20 2008 : 11:43:39 PM
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| Grab Their Weapons? Oh, you are an American. |
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Aaron Cake
Administrator
Canada
6717 Posts |
Posted - Dec 27 2008 : 11:02:49 AM
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If someone breaks into my place, I'll be grabbing for my weapon as well and I'm not even American.  I have cameras set up at the front, back and side of the house. |
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Contact Switch with delay...I need your help
