Development of a Simple Sound Activated Burglar Alarm System

Discussion in 'The Projects Forum' started by killoder, Mar 30, 2012.

  1. killoder

    Thread Starter New Member

    Mar 30, 2012
    I am currently doing a school project , and i have decided to do a burglar system. I have found this scheme: and started until i reached the flip-flop. Many problems are around the flip-flop. It says pin 7 is connected to regulator but in fact, pin 7 is Vss. Also, it does not mention any other pins used. In the oscillator, it does not say which pins are used to connect to the diodes. The resistance near the transistor 2SD400 has no informations.

    Can anybody help me with this?
  2. Audioguru


    Dec 20, 2007
    Do not copy that incomplete circuit that has errors.
    Look for a better circuit or design your own.