With Instructables you can share what you make with the world, and tap into an ever-growing community of creative experts.
Tell us about yourself!
here is the picture
thank you for the info, my alarm finally works, but there's a new problem, when you interrupt the beam alarm goes on but it turns off by itself as you stop interrupting the laser beam. it supposed to keep buzzing until i manually reset it with the switch, but it's not. according to my friend he said that the timer has no reset option, but your post tells the otherwise, how can i fix this? thank you once again for answering my questions
There it is, Vcc is fine(6v) but it keeps buzzing even when i close(no light) the photoresistor (which i manage to find, and i'm not sure what its resistance my friend said its 10k) r2 is 10kohm and r1 is 100ohm i follow the exact diagram u posted, please help me its due next week.
I try making it, I still failed, These are my components, 2 100ohm resistor Phototransistor 2 terminal555 timer, SwitchTried on breadboard still not working
I have pictures of it might be hard if post it here can i send it to your email instead? Im building this for my class project and i need your guidance, im still new it this things
I have a question, I can't get a photoresistor, instead i bought a phototransistor, what should i have to accompany it and is the step on making it different? Thanks and sorry for bad english
Let your inbox help you discover our best projects, classes, and contests. Instructables will help you learn how to make anything!
© 2016 Autodesk, Inc.