hey guys, i want to make a smoke detector using mq2 and dht11 and send the alarm by sms. the condition is when a temperature reach 40C and there's a smoke detected then the arduino will sends a message. is it possible to make that project?
and do u guys have a references that i can use? thank you 
one more, can i give just HIGH variable for mq2?
Change the title of your Thread to "Smoke detector and SMS" and you might get the attention of people with specific experience.
Provide links to the datasheets for the devices you are thinking of using so readers here don't have to waste their time looking for them.
What you want to do should be perfectly feasible, but I have not used any of the parts you are interested in.
I'm not sure there is any value in an SMS about smoke. If you are far enough away to need an SMS you are hardly going to be able to do anything about the smoke.
...R
hey guys, i want to make a smoke detector using mq2 and dht11 and send the alarm by sms. the condition is when a temperature reach 40C and there's a smoke detected then the arduino will sends a message. is it possible to make that project?
and do u guys have a references that i can use? thank you
Arduino is not going to send message by itself you will need to first of all get the MQ2 sensor prepared which requires various steps such as pre-heating etc and then you will have to test it to code what Analog values are putup.
To send messages from arduino you will need a grps or 3G module like the SMB5100 or SIM900 or SIM300 or ETC.