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General suggestions or questions about the SparkFun Electronics website
By ISOTropic_Pixel
#152831
I am need of powering a DSLR for extended periods outdoors in the winter, so portability is critical.

I thought about an off-the-shelf inverter along with the factory AC power supply, but this is somewhat more money than I wanted to spend. And, the inverter and AC power supply are huge which sort of kills the portability.

I would like to utilize different, large capacity, batteries anywhere from a 12v motorcycle battery to just a bunch of stacked AA cells that I can throw under a coat sometimes. I am not sure how to regulate these sources for the camera.

The camera uses 7.4v batteries that I've seen variants ranging from 1900-2500mA, but I don't know how many amps the camera actually draws or requires for normal operation.

Is this really just a matter of slapping together an LM317 with a proper resistor for 7.4v and not worry about things like excessive current draw from the camera? If not, what exactly do I need, and are there any kits known to exist for this purpose?


Thanks much.
By CS Paul
#152879
You might try posting over in the technical side - posts here are more specific to the SparkFun website, so people who can help you might not see this here.
By jremington
#152895
If the camera has a power jack (and you have or can buy the AC adapter) then you just need to measure the voltage supplied to the camera and average current drawn by the camera under the conditions of intended usage. This will require you to cut the power cable so that you can measure the current.

With that information, together with the proposed time period for unattended operation, it is straightforward to come up with an appropriate battery powered regulator.