I want to be able to pull my carputer out of the car and power it up in the house in case I need to work on it. I took the keyboard, usb, led and switch outputs and ran them into a 25 pin connector. To be able to run it in the house I made a little circuit board adapter. I have the mounting in the car just about done then I'll wire it up.
On the left, the little board with the green terminals is the shutdown timer I made. When the key is shut off one relay pulses the ATX power switch and the other relay keeps the inverter on for about 40 seconds. Here's the schematic, I used different ideas from different circuits I found here and on the web.
Some people have looked at it and don't understand how the second relay works. In my car the key on power lead has enough of a load on it that when the key is turned off terminal 2 pretty much sees ground, which causes the 2nd relay to pulse. when the first relay times out the whole circuit goes dead and the caps are all discharged. I think I'm getting the hang of this carputer stuff
-Jesus- King of Kings Lord of Lords
Originally Posted by turbochris
Pretty ingenious. Thanks for sharing.