figuring out how to delay a circuit
I have finally got all of my stuf to install my labtop in my car but i have a problem. I also have a external HDD going to the radio through the usb port. ive wired it to work off a power inverter and the power inverter is to be controlled by a relay that will be turned on by the acc power of the radio. The acc power is just to signal the relay not to power it. This way i wont have to switch on my power inverter every time i get on the car or accidentally leaving it on. the problem comes from when i start my car the starter requires a bunch of power thus creating a unstable voltage. im looking for something that as soon as i start the car will turn on the power inverter. i was thinking maybe something like a delay relay of sorts id rather do it kinda cheap as well i didnt know if anyone knew how to make one cause id be happy to make it rather than buy it.