you..........

I haven't got any diamond watch. Its an ordinary one bought for only 200 rupee from a Pathan..... you know.

you can add another novel method to the cheap timebase. connect a bare end wire to the Interrupt. Connect another bare end wire to ground. Bring the bare ends of both wires close (but with open gap) and place the gap under the Tap of your wash basin in bathroom. Open the tap slowly so that it only starts dripping. every drop that goes down will cause a transition interrupt. you know.

Practice well until you get 1 Hz..........

Don't forget to Lock the bathroom properly ater setting the clock.

Ask a chemical engineer, taps leak with a high degree of accuracy. Its a matter of CV (coefficient of valve).