Raspberry PI Powered by AC, Automobile Accessory or Rechargeable DC source
The eventual result of this instructable is, a portable (self powered) raspberry pi system to run field experiments.
Small inexpensive portable system that includes, Computer (RPI), Monitor with Audio speakers (Secondary screen from refurbished Auto DVD player $29 including the DVD player to be repurposed), wireless keyboard with touch-pad (FAVI or alike micro keyboard).All powered by my rechargable compressor/ 12 volt power source ($39 and I already had it for use with my pneumatic cannon). The compressor has another use filling tires when away from power but that was just an excuse to buy it. I also plan to have an AC supply make from a USB Hard DIsk programmer (12v and 5v 1.5A each convenient).
(new my UPS battery backup died, but the battery is still good I will make a pigtail to auto accessory adapter)
Yes I know you could use a Atrix Lapdock (I have one it was only $35 and use it for demos, but this is more fun and less fragile, if you have one you know). Besides it just looks like a laptop, and kind of takes away from the mad scientist image I am shooting for.
So Lets get going..
Raspbery Pi and case (see my instructable) http://www.instructables.com/id/Raspberry-PI-case-with-built-in-surface-mount-for-/
Auto DVD player secondary screen (mine was from Cow Boom for $29)
Keyboard Favi wireless micro keyboard
12V Power Supply rechargeable: Home Depot Link
PC Hard drive power extender cable male and female.
Sabernet hard drive programmer power supply.
USB car charger (make sure you can deliver at least 1 amp otherwise it is useless).
radio shack car lighter slitter (you will be cutting one off but so be it.)
12 volt connector for your dvd second screen ( I had one from some other device I had, junk drawer)
Micro USB connector, cut one of your cables but my suggestion is to buy one of the "charger connectors" from radio shack, the RPI needs current and the more you can deliver the better it will perform.
Optional WIFI I use a AM150 it can run off the PI with no power issues (this is big).
Latest Raspbian Build ( I won't go into this part it is part of owning a PI).
Various connectors cable depending on your screen:
Stereo jack (from an old head set or a common connector from Radio Shack, I went for this they are cheap and easy to assemble).
I used intercom cable for power the stuff I have can is 24 guage more than I needed.
Composite video male to male.
Usb Type A to plug into the charger.
Wire strippers and snips.
Soldering Iron / solder (you can do all this without it but the cost of cables and connectors gets high)
Glue Gun / glue
I am an older engineer from the days when the ability to solder was taught in EE labs. Now here in the US we don't graduate as many EEs and almost all of those never touch any analog power circuits filters or antennas (about the only place you still solder). OK, I will get off the soap box.
NEW: Added video here to see if you are interested: