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Wiring A Battery Powered Device In

Duncan

By Duncan,
in Car Audio & Electrical

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Duncan Grand Master

Duncan

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OK I have a car electrical question and this forum is the closest I can find.....

I have a new video camera for the race car, butit only runs on 4AA batteries, it doesn't have a power input socket of any sort.

In my previous DV camera setup I used a voltage regulator to drop the power to the correct volts (4.6 from memory) and wired it into the car's system.

So....my question is, can I replace the 4xAA batteries (1.5v each?) with a 6v supply, reduced from the car's 12v system? If so do I just put power to the + of the first battery slot and earth to the negative of the last battery?

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Chris Rogers Grand Master

Chris Rogers

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do you know how much current it pulls at startup? if you do and its under 1A a 7806 on a decent heatsink will do it. if its over 1A then look up current bypassing or high current voltage regulators in google that should net a schematic for it. make sure you fuse the thing with a fast blow fuse and a crowbar diode (google this.) for safety. that will save the camera if hte circuit goes down.

Duncan Grand Master

Duncan

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Hi Chris, thanks for the quick response....

No I don't know what current it draws at startup (and I guess the manual probably won't say). Can I just measure it with a multimeter (connect 4 batteries and the mm into the battery area) or is there another way to find out?

I guess by 7086 you mean one of these guys:

Z0532.gif

I was kind of assuming I would need something more complex but this would be great. And what sort of size is "decent" for a heatsink? Also, I think the 7806 reduces voltage by a fixed amount but the car's supply varies from 12-14.5v, is that a problem?

I take it one of these is another option that would cover the required amperage? 5-12v selectable, up to 5amp. I already have one of these in the car for the old camera setup

product_11337.jpg

But the real question was, can I just wire the voltage directly to the camera's aa battery compartment + and - terminals once I have the right voltage

Sorry for the very basic questions but I know sfa about electrics

Chris Rogers Grand Master

Chris Rogers

Posted
Posted

your second option would do it. I was making one from scratch. as for wiring it in - you *could* make a fake battery and stick two nails on the ends with the appropriate wiring.

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