Intruder alarms etc

[Mps6]

just wondering as to people's experience with alarms, had a few explores cut short by alarms. The first of which was very obviously a ligament security firm set up, but the second one we encountered on a different location was fairly quite and sounded like it was more a deterrent more then anything. Anyone else come over possible deterrent alarms, or anyone stuck around long enough to find out.

 

[DrGonzo]

Depends on the place really, 95% places I have been to either the alarms are silent (doubtful) or they don't have them. I recently went to a house that had been compulsory purchased by a mining company where the door had been left open, the house was alarmed but we only had what I guess was a warning tone to show that it hadn't set properly. Left anyway as it was a pretty busy area. Other times the alarms have been going off when we arrived, just hung out for a bit to see if anyone would respond, when no one did we went in.
I'm not sure quite sure on whether this would be allowed and it's not something I have done when out, but one could just put some tape over the front of the acess PIR's real quick, leave wait for the alarm to be re-set or quit then return without triggering them.... Anyone have any thought's on that?

 

[bagpuss_24]

Quite an old post; though will add my tuppence.
In my apprentice days, worked for a (then) large and reputable Intruder Alarm installer (AFA-Minerva).

In the early days of electrical Burglar Alarms as we know them began after WW2; these generally were a "silent" system; that when activated, would not make any noise - but would signal the local police station.
Crime figures dropped.

Criminals (always being 1 step ahead) then would open a door/break a window on a building and then sit round the corner to see who or what turned up to investigate - that way they knew if it was linked.
Bells were added on some systems - and back then, people took more notice of them.

Jump to the early 1960s - there were 100s of Alarm installers popping up - and a large percentage being cowboy firms - and of course, came the false alarms.
Police refused to turn out to systems with a constant false alarm.

So - regs were brought in - and strict standards for installation. Direct links to Police stations were becoming expensive to install/maintain and operate.
So many large companies (AFAs / Rely-A-Bell etc) set up their own monitoring stations. Again these weren't cheap to subscribe to.

During the 60s & 70s, you would only really find a Bank / Post Office / Jewellers / Large good wherehouse linked somewhere.
Everyone else with an alarm would have a bell that rang locally - just basically making a lot of noise!!!

Jump to the 1990s and more recently, the regs have changed, and insurers insist on having the system linked somewhere- either via a Landline dialler, or even via a network/Wi-Fi.

Derelict buildings with a functional alarm, may be linked elsewhere - albeit to a Security Firm or even a Pager to the on duty guard.
The old way - would be to take the phone off the hook to engage the line (it wouldnt be able to dial out).
The other was connect a battery to the outgoing line!

Both of the above are old methods tried and tested by criminals (I have seen this when had to repair systems) - and wouldn't work on any system installed today, as such equipment is non-compliant.
So - before I get shouted at - I am not encouraging criminal actions!!!!! ;-)

If anyone see's any old Alarm equipment (functional/non functional) it'd be nice to see some pics of such kit.
Some AFA kit is still about - though not working.

To Tape a PIR - many are "Dual Tech" sensors - and also monitor Ultrasonic Noise too; so blocking the "eye" sensor wouldn't work!
Cutting the wire, removing any cover would also set it off.