Thread: Laptop automatic startup using a single shot relay

U3 is a simple SPST 12V relay. 12V (or there abouts) across the Coil (K) closes the contacts, which are wired across the power button on the laptop.

My reasoning for continuing the pulses is that One-press starting is not entirely reliable, because of the lower battery voltages present during and about 5 seconds after cranking. This is why I have it pulse every 4 seconds, IF THE COMPUTER ISN'T on yet. I will be building the same thing for my monitor (which doesn't have an always on feature).

thanks for the clarification.