hii i am Radhika patil I would like to get details on ellectronic watch dog advantages ,disadvantages and literature survey..my friend said electronic watchdog advantages disadvantagesunction will be available here and now i am living at pune and i am in the college PCCOE. ....i need help on ......etc
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Electronic watchdog
Here is an electronic watchdog for your house that sounds to inform you that someone is at the door. The circuit comprises a transmitter unit and a receiver unit, which are mounted face-to-face on the opposing pillars of the gate so that the IR beam is interrupted when someone is standing on the door or passing through it. The transmitter circuit (see Fig. 1) is constructed around timer NE555 (IC1), which is wired as an astable multivibrator producing a frequency of approximately 38 kHz. The infrared (IR) beam is transmitted through the IR LED1.
![[Image: Electronic%20watchdog%20%201.png]](http://www.muengineers.in/_/rsrc/1467886106552/extc-project-list/electronic-watchdog/Electronic%20watchdog%20%201.png)
