{"product_id":"us-police-siren","title":"US Police Siren","description":"The \u003cstrong\u003eUS police siren circuit\u003c\/strong\u003e presented in this schematic is an alarm circuit that produces the sound of the US police. This \u003cstrong\u003eUS police siren schematic circuit\u003c\/strong\u003e is based on the 555 multi-vibrator. To build this US siren circuit we can use two 555 IC’s or one 556 IC which contains two 555 chips in one package. Synchronously with the siren sound, a lamp will flash. \u003cbr\u003e\u003cbr\u003e Both \u003cstrong\u003e555 IC’s timers\u003c\/strong\u003e are configured to operate as astable multi-vibrators. The first-timer is configured to supply a \u003cstrong\u003erectangular signal of about 2 Hz at pin 9.\u003c\/strong\u003e The lamp is switched on and off by way of the power transistor. The second 555 is configured to supply a square wave at pin 5 that drives the loudspeaker. The loudspeaker of the siren must have a value between 8 and 32 ohms.\u003cbr\u003e\u003cbr\u003e\n\u003cdiv class=\"product_info\"\u003e\n\u003ch3 class=\"sing--sub-heading\"\u003eBlock Diagram\u003c\/h3\u003e\n\u003cdiv style=\"text-align: start;\" id=\"p_info\"\u003e\u003cimg alt=\"US-Police-Siren-block-diagram\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0587\/2130\/4757\/files\/US-Police-Siren.jpg?v=1633520380\" 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 title=\"YouTube video player\" src=\"https:\/\/www.youtube.com\/embed\/LVxvmzNH3d0\" height=\"400\" width=\"800\" allowfullscreen=\"\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture\" frameborder=\"0\"\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","offer_id":40708890722485,"sku":"LGKT124","price":499.0,"currency_code":"INR","in_stock":true},{"title":"READY TO USE","offer_id":40708890755253,"sku":"LGKT124_R","price":649.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0587\/2130\/4757\/products\/us-police-siren-kit.jpg?v=1633521284","url":"https:\/\/kitsguru.com\/es\/products\/us-police-siren","provider":"KitsGuru","version":"1.0","type":"link"}