Looking for a tamper proof electrical circuit

Basically I am trying to design a polycarbonate box with GPS antenna and VHF antenna. The idea is to sound off an alarm when there is a burglar. When the burglar tries to cut the wire (with a 12-V power supply), a back-up battery as an alternative power source is used.

Use a off the self alarm installation cheaper and in a temper proof box.

There is an article in the Oct 2012 issue of Nuts and Volts (pg 40 Remote Data logger and Surveillance Cam) that might supply part of your solution. It shows how to use a Verizon Samsung Gusto 2 no contract cell phone to set up a remote monitoring station. It could easily be adapted to your purpose.

I tell you how to do this

Use a software approach ( To protect the design itself and the software ) Use a pic micro UV erasable chip You can buy these from Micro Chip or Rs components or Farnel Then what you do is incorporate part of your alarm software into the chip itself Tamper proof is operated via micro switches on the lid and so that if the unit is opened It automatically wipes the code Triggers a UV diode and erases the chip (Software protection)

Next to protect the 12 volt line incorporate a back up battery 5 volts or what ever it needs to operate the Micro Chip ( This will kick in if the 12 volt line drops below the 5 volt threshold (Battery Back up ) Mains backup

Of course nothing is ever fail safe but you can do your level best as near as dammit to stop them

If you really want to get clever with this What you do is incorporate UV detectable spray inside the house so that (On entry attempted ) even outside if you like ) for unauthorized intruders Use UV spray mechanism designed to go off very much like an airbag in the car to identify clothing etc on the intruder These cwill identify clothing and leave permanent markers when making contact with intruders skin personally i would like to use flipping acid with them to be honest but their you go

There are lots of articles and methods that you can use

One of the last methods I was forced to use was wire the bloody doors and windows to a 240 volts supply live 24 amp AC on an attack at my last premises

The law didn't like it to much but they thought a little bit better after seeing what I did and will do if need be

In South Africa they mount flame throwers under the vehicles because of the problem with Car jacking "Works well for me " burn them to death love it

If I had my own way Id have IP controlled machine guns inside my bloody premises with auto detect on movement like the wee games consoles

That Unfortunately is me I believe very firmly in the right to self defense and the right to bare arms

Not that I give to hoots about the law when it come to self defense its either me or them and as far I'm concerned when it comes to unprovoked attack Its my own life that's important if they wind up dead that's just plain bad bloody luck

If you need to blow the bastards up bleedin blow them up and incinerate them !!

Correct I don't give a toss stuff the political correctness