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Alarm Clock to Turn on Stereo

Posted: Mon Oct 04, 2004 12:28 pm
by Vincent
For some reason, I am not waking up to my alarm clock anymore. It is pretty loud already.<p>I want to wire it to turn on a home receiver and a CD player that will play a CD to wake me up. Obviously, this is partly for fun since there are other approaches that are easier.<p>With DC, I would need a relay that taps into the wire that receives power when the alarm is set off. Is there another way to do it externally? Can I use a microphone set near the clock that turns on the relay(?) with the back emf? <p>What kind of object is similar to a relay for alternating current? Or does a high voltage relay still work? <p>The alarm beeps in pulses now. How can I keep the AC power going to the home receiver constantly after it senses the first pulse?<p>Thanks. Keep it simple since I don't know a lot about electronics. :)

Re: Alarm Clock to Turn on Stereo

Posted: Mon Oct 04, 2004 1:18 pm
by Mike
Well, you could connect the speaker wires to a rectifier to turn the AC sound to a DC voltage possibly (not sure if this will work though) then rig a relay to some kind of circuit to trigger the amp (possibly a hacked Clapper)

Re: Alarm Clock to Turn on Stereo

Posted: Mon Oct 04, 2004 1:45 pm
by Chris Smith
You can set up a 555 as a sound receiver, and let that trigger the rest. if your alarm is loud like you say, it makes it all the easier. Any mic that produces a voltage, can be fed into a 555 for triggering.

Re: Alarm Clock to Turn on Stereo

Posted: Tue Oct 05, 2004 3:26 am
by Vincent
What is the 555? An IC?<p>Do you think I will be able to find it at Radio Shack or over the net?<p>Thanks!

Re: Alarm Clock to Turn on Stereo

Posted: Tue Oct 05, 2004 8:43 am
by jwax
Set up your PC to Auto-Dial your phone at your wake time.

Re: Alarm Clock to Turn on Stereo

Posted: Tue Oct 05, 2004 7:40 pm
by paulrevelcet
Yes radio shack part number 276-1723 cost is 1.49 cents. try this link for more on the 555 ic.web page

Re: Alarm Clock to Turn on Stereo

Posted: Tue Oct 05, 2004 8:56 pm
by Chris Smith
Radio shack has the chip and great book on the subject, by Forrest Mimms. About 2 bucks.<p>If you cant find the book I could forward a single copy of a blue print on how to modify the chip for just about anything. <p>The 555 can be configured to do over a thousand things.

Re: Alarm Clock to Turn on Stereo

Posted: Wed Oct 06, 2004 10:01 pm
by Vincent
Cool<p>If I don't find the book, I may need the blueprint.<p>Thanks!