In this project i will demonstrate how to convert a common alarm clock into a timer.
Than we are going to use motor from old cd-rom to trigger simple fountain alarm.
Step 1: Clock Circuit
Open the clock mechanism.You will notice there is a mechanical switch that connecting ground pin to a integrated circuit.
We need to cut that connection to ensure that we will not damage IC.
Than just solder a wire next to a switch.Other wire we need is a ground.That ground we need to connect on the ground on our circuit as well,and it's not recommended to mix wires. So the ground stay ground.we can also disconnect a ground from other side as well so we don't need to pay attention to this.
Since the switch is not insulated i don't recommend using more than 12v,and due the cheap construction i would rate it at 500ma. if you need to switch heavier loads than you need to install a relay.But for small loads like cd-rom motor is OK.
Step 2: Assembly
I glued a cap from small pill bottle on a gear wheel and wrap copper wire around.Bend copper wire so it can reach for the limit switch in desired position.Limit switch that i use is savaged from old printers and it is normally closed.
i used soldering iron to drill small whole and than place vinyl pipe thru the whole.
Step 3: Dress Up