Hacking An Alarm Clock Answered
My sister (yes, the one for whom I made earrings) wants me to modify an alarm clock to run a small electronic device when it goes off. Preliminary research has given me two methods:
1) A digital clock with a 555 timer circuit
In this setup, a 555 timer circuit is used to translate the signal to an alarm speaker/piezo disk into a relay. When the clock goes off, the relay clicks, and any electrical device that is run through the relay has power.
2) An analog clock with a transistor amplifier
In this version, the analog clock seems to just have a straight DC output to the alarm. The transistor is used to amplify the DC to drive the motor of a fire bell.
Which of these would be easier to implement? The device I am supposed to use runs off of 3VDC, so I was just going to run the power line through the relay or through the transformer.