Hi can anyone help with this? (pointers / suggestions?)
I know you power an Arduino off a USB, and I also know you can run it off a 9v wall wart.
Has anyone ever run it portably? ( with a battery e.g 9v / other? ) if so would any kind soul let me know if it needs a regulator circuit, and if it does where could I find a copy?
Are there any pitfalls to doing this sort of thing? Battery life, life of the Arduino etc?
Thanks in advance. McP
RobMcp:
Hi can anyone help with this? (pointers / suggestions?)I know you power an Arduino off a USB, and I also know you can run it off a 9v wall wart.
Has anyone ever run it portably? ( with a battery e.g 9v / other? ) if so would any kind soul let me know if it needs a regulator circuit, and if it does where could I find a copy?
Are there any pitfalls to doing this sort of thing? Battery life, life of the Arduino etc?
Thanks in advance. McP
The easiest way to power an Arduino board with batteries is by wiring it to a compatible plug and using the arduino external power connector. Your battery pack would need to have a voltage of between 8vdc and 12vdc. The arduino on-board voltage regulator will change this to +5vdc that the board runs on. Using a standard small 9vdc battery can work but such batteries can supply such low current as to not be very useful if you are wiring anything external to the board like leds, etc.
Battery life depends on how much current your board and external components draw. The basic board draws about 50ma or so. Battery capacity is rated in mah (milliamp/hours) and that along with how much current draw of your project, can be used to calculate how long it will run before the batteries need replacing or recharging.
So give us a clue of what all your board will be performing and wired to, and how long a minimum battery life you are looking for and maybe we can make more detailed recommendations.
Lefty
Thanks Lefty for the helpful reply.
Didn't have anything specific in mind (yet) just wondered if the word portable could be used with an Arduino.
I've had a duemillenove for about a year, and still have not quite got to grips with it (lack of spare time)
I have a virtual hobby, have all the kit and the ideas but no time to actually carry out ideas! Sad life when you're busy.
Thinking about using it with a standard 9v battery would just be for short monitoring or testing sessions, not driving large loads or anything lengthy.
Thanks Again.
McP
I have a virtual hobby, have all the kit and the ideas but no time to actually carry out ideas! Sad life when you're busy.
Well retirement 3 1/2 years ago helped me with that problem. 
Hi! I am working on a project with 16 LEDs (thanks to a TLC 5940) and 16 pressure sensors (thanks to n.2 4051) + 1 vibromotor (301-101) and I'd like to make my Arduino portable. Is it the 9v battery a proper solution? If not can you give me some suggestions of which could be a cheap and fast one? I don't need the battery to last long, and it's no big deal to change/recharge the battery. If the life span is within 2hours for me is fine.
Thank you.
Is it the 9v battery a proper solution?
No.
I would use a bunch of AA batteries, they have much more current capacity
How should I connect them together? If I am not wrong they should be like 6 x 1,5V AA batteries, right? Is there a tutorial I can find on how to connect them together and having the two wires to solder on the center positive jack to plug into the Arduino?
How should I connect them together?
In series.
And connect the negative to ground and the positive to the Vin pin.
Is there a tutorial I can find
It's on the same page as how to breath in, and then after a short pause out. Repeat if you don't want to die.
Pricless
This might sound as a stupid question but... why positive on Vin and negative to ground instead of using a jack to plug in?
Because then you don't have to have a jack plug nor search for a tutorial on how to solder two wires to it.
You also have a series diode in line with the jack plug that robs you of 0.7v. You only need the voltage to be about 6.5V for this o work you don't need the full nine volts.
I have built "Bulbuino"*, an intervalometer for photography. It runs off a 9V block that powers an Arduino Pro Mini through the Pro Mini's regulator. In this highly inefficient setup (9V battery on a 3.3V Arduino!), the battery reliably lasts about 24 hours. I have seen 48 hours in tests, too. Mind you, though, that the Pro Mini does not have a USB interface and wastes no power for that. It also only runs at 8 MHz and hopefully uses a little less power than the full 16MHz version.
The Bulbuino has a trivial voltmeter so the user can track how much juice is left in the battery.
You should not expect miracles from a trivial setup, but a 9V block will probably last at least 12 hours on a Duemilanove/Uno. Which may or may not be enough for your applicaton.
(Edit: Fixed time specifications after reading my own notes.)
you can very easily just get a rechargeable 9v battery pack. works well and is portable for your project