Jose Pino
Usually quartz clocks breaks easily (specially if these are made in china) after a while. The gears loses lubrication and the dust gets the job done. Fortunately, the electronics of the clock works for many years without problem, so you can "hack" a quartz clock to get a timebase generator.
Here is the "victim". A clock can be purchased for only $4 USD, sometimes it can be purchased for only $1 USD.
The clock mechanism only have three tabs and can be open easily.
You can save the gears, it may be useful in the future.
Here is the part that we are looking for. The timebase generator.
As we don't need the coil, we have to remove it. Remove it carefully, it will be used for a future project.
This is the modification that need to be done. We need to diodes (1N4148 works great) and 1 k resistor. The resistor will reduce the current so the circuit can work from three volts to five volts.
Here is the circuit with the modification. The photo shows the two diodes and the 1 k resistor can be mounted in the circuit board.
This photo shows the circuit under testing. I used 3 Volts and one led. The led blinks exactly one time per second.
Here is an explanation how the quartz clock works:
As you can see, the circuit generates a pulse every two seconds on each connection of the coil, it makes the round magnet to turn half cycle for each pulse. So, using diodes adds each pulse to generate one hertz. (1 Hz = One pulse per second.)
