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Typical alarm zone to trigger a 555

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Hey all, I tried to post this a couple weeks ago but it hadda be changed to a JPEG, anyway here it is:

The 9V charges the capacitor and holds the output on terminal 3 low (0V) when the magnetic door/window contact/s is broken (open circuited) the discharge brings pin 3 (output) high, sending 9V to the base of the NPN resistor which in turn goes to a common relay that will latch and send power to a digital dialer and a loud db siren. This is the circuit I wanna use for all zones including door entry and exit and 24 hour tamper, in the case of the entry circuit/s I'll have a 30 to 60 second time delay to disarm the system using a higher value resistor (external) if the code isnt entered in the time allowed the system will go into alarm mode. As usual I'm a novice and want you guys/gals input on what ya think. Thanks in advance and looking forward to your thoughts and or idea's. Happy belated St Patricks Day !!! Jim
 

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ericgibbs

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hi Jim,
Are you asking for the circuit design to be checked out.???
 
hi eric, pretty much yes. before i put it together i like to know in theory from u guys. theres prob other ways to do it, i thought a higher value resistor to ground to a transistor base would work as well. and when the contact opened it had an easier path, yea i need input on stuff. dont forget im a controls electrician not an electronics specialist, thats why i always ask.
 
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