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Burglar alarms

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Jan12-14, 10:40 AM
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I don't understand what exactly a transistor does in a burglar alarm. I read somewhere that this is its application as a switch but isn't it the LDR which works like that in this particular circuit? It would be really helpful if someone could explain the working in detail, I can't seem to find any proper explanation on the net.
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Jan12-14, 02:52 PM
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there's probably a few individual transistors and a number of IC's that contain many transistors in any given alarm unit.
Your question is pretty meaningless till you give us more information to go on
Do you have a specific alarm unit?
do you have a circuit diagram for it so we can see what specific transistor(s) you are referring to ?

Transistors can be used ( amongst others things) as a basic switch


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