hi everyone,i'm building a smoke detector project using a light source and an LDR.can someone pls help me with this project and also if there are better ways to build this detector,pls let me know. thank you.

 

Is this for use as safety equipment or just for educational purposes?

 

Is this for use as safety equipment or just for educational purposes?

My self i wouldn't trust a home made digital alarm clock to wake me up in time for work let alone a home made smoke detector. For the OPs safety I hope this is for educational purposes.

 

My self i wouldn't trust a home made digital alarm clock to wake me up in time for work let alone a home made smoke detector. For the OPs safety I hope this is for educational purposes.

pppbbbbbtttt!

Me too!

If I built a smoke detector, it probably would not go off until the firemen were hosing it with water.

 

As long as you're looking into this for recreational purposes, you might start with an LED and a photo-transistor, or similar arrangement (you're going to need some sort of emitter and detector). The detector is going to be the tricky part, you're going to need some sort of comparator to distinguish the smoke signal(hurr) from the normal output of the emitter.

I once made a simple circuit to send analog audio over a laser beam, using a photo-transistor as a detector. I found out pretty quick that smoke or vapor (such as dry ice used to show the laser beams) essentially puts a lot of noise in the signal.

 

thanks alot for ur posts. yes,its for educational purposes but u guys make it look like a home made smoke detector can never be effective.if thats true that wats d purposes of all d educational projects if the cant be used i real life situations. and back to my question,is there any other way to build a smoke sensor without using LDR.i need a more sensitive component.can anybody pls suggest one to me?