{"product_id":"door-knock-alarm-with-timer","title":"Door Knock Alarm With Timer","description":"This \u003cstrong\u003eKnocking Alarm With Timer\u003c\/strong\u003e uses the piezoelectric element of a piezo buzzer as the input sensor. The piezoelectric element plate is a patch at the center of the door wing by using cello tape. Apply a small quantity of adhesive at the edges between the plate and the door. The \u003cstrong\u003eAlarm With Timer\u003c\/strong\u003e is designed with extending wires about 1-1.5 meters from the piezoelectric to the circuit. IC NE555 is configured in monostable mode.\u003cbr\u003e\u003cbr\u003e When this \u003cstrong\u003eLow-cost Timer Circuit\u003c\/strong\u003e gets an input pulse, its output goes high for a period set by the Variable resistor, resistor, and capacitor. IC UM66 is used as a melody generator. When the door is knocking at the pizza plate generates an input pulse, which is amplified by the transistor. The \u003cstrong\u003eDoor Knock Alarm's\u003c\/strong\u003e amplified signal triggers the timer IC NE555 and its output pin 3 goes high to enable the melody generator. After the set time period, the melody sound stops.\u003cbr\u003e\n\u003cdiv class=\"product_info\"\u003e\n\u003ch3 class=\"sing--sub-heading\"\u003e\n\u003cbr\u003eBlock Diagram\u003c\/h3\u003e\n\u003cdiv style=\"text-align: start;\" id=\"p_info\"\u003e\u003cimg alt=\"Door-Knock-Alarm-With-Timer-block-diagram\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0587\/2130\/4757\/files\/Door-Knock-Alarm-With-Timer.jpg?v=1632825473\" style=\"float: none;\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"product_info\"\u003e\n\u003ch3 class=\"sing--sub-heading\"\u003ePhysical Attributes\u003c\/h3\u003e\n\u003cdiv id=\"p_info\"\u003e\n\u003cul class=\"pro-ds\"\u003e\n\u003cli\u003eDimensions (cm) L x W x H : 20 x 15 x 5\u003c\/li\u003e\n\u003cli\u003eWeight (gm): 200\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"product_info\"\u003e\n\u003ch3 class=\"sing--sub-heading\"\u003eProduct Video\u003c\/h3\u003e\n\u003cdiv id=\"p_video\"\u003e\u003ciframe width=\"800\" height=\"400\" src=\"https:\/\/www.youtube.com\/embed\/wSREw4vaJog\" title=\"YouTube video player\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cdiv id=\"p_video\"\u003e\u003ciframe width=\"800\" height=\"400\" src=\"https:\/\/www.youtube.com\/embed\/6rmErwU5E-k\" title=\"YouTube video player\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003cdiv id=\"p_video\"\u003e\u003ciframe width=\"800\" height=\"400\" src=\"https:\/\/www.youtube.com\/embed\/Fp37DPZVdRI\" title=\"YouTube video player\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" allowfullscreen=\"\"\u003e\u003c\/iframe\u003e\u003c\/div\u003e\n\u003c\/div\u003e","brand":"KitsGuru","offers":[{"title":"DO IT YOURSELF KIT","offer_id":40708870897845,"sku":"LGKT044","price":549.0,"currency_code":"INR","in_stock":true},{"title":"READY TO USE KIT","offer_id":40708870865077,"sku":"LGKT044_R","price":899.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0587\/2130\/4757\/products\/Door-Knock-Alarm.jpg?v=1632825847","url":"https:\/\/kitsguru.com\/de\/products\/door-knock-alarm-with-timer","provider":"KitsGuru","version":"1.0","type":"link"}