DIY 12V to 8V DC powerconverter to power a Canon 1000D

[astrovirus]

Besides working on my Balcony Micro Observatory, I'm also putting some small amount of time in preparing to modify a second Canon camera to use alongside my trusty peltier cooled Canon 350D. However, my voltage regulator that powers my 350D can not be used on the 1000D that will be modified as it has a different battery. So, I could just have modified the battery line to accomodate both the 350D adapter and a new one for the 1000D, but instead I just made me a whole new one so I can use then side by side if I want to. Costs only 5 euro for the parts en another 5 for the case, and uses a 7808 voltage regulator with 2 capacitators (1 and 0.1 micro farad) and a diode to prevent damage due to misconection on the main 13.8 V DC PSU. Adapter was salvaged from an old dead battery. Works like a treat.

[Bizibilder]

Could you provide a simple diagram please - it looks a useful bit of kit that is simple to make.

[astrovirus]

Hope this works, as the tiff file looks OK, but I cant save it as jpg because the background turns black for some reason. This should be the diagram, only with the indications LEDs left out for this one.

12to8VDC_schema.tif

[russellhq]

I used one of these for my camera supply. Cheap as chips

http://www.ebay.co.uk/itm/141210161794

[Bizibilder]

Here you go:

And thanks - very useful!

[Bizibilder]

Russellhq - with one of those do you simply put a voltmeter across the output and run the camera from that as well - so you can "dial up" the voltage you want - or am i being too simplistic? (I know less than a little about things electrical!).

[russellhq]

Yeah, that's all you have to do. It was pretty simple.

[Bizibilder]

I may get myself one - or two!!

[Lonestar70]

Russellhq - with one of those do you simply put a voltmeter across the output and run the camera from that as well - so you can "dial up" the voltage you want - or am i being too simplistic? (I know less than a little about things electrical!).

Hi Roger,

With this circuit the 7808 will only output +8v, there is no adjustment for voltage in the circuit (no dial up)... so, other than as a double check after building it, there is no need for a voltmeter on the output.

I should also point out... if you use a higher input voltage than 12 volts (max +36volts) you will need to fit a heat sink to the 7808 as it will get quite hot dissipating the extra voltage.

Hope this helps.

Best regards.

[astrovirus]

I use my 7808 with 13.8V DC input, but still use a heatsink just in case, as the camera may pull the max 1 A current sometimes, which will also makethe 7808 potentially hot.

[pete_l]

Russellhq - with one of those do you simply put a voltmeter across the output and run the camera from that as well - so you can "dial up" the voltage you want - or am i being too simplistic? (I know less than a little about things electrical!).

Yes. that's all there is to it. If you get the version with an inbuilt LED display, you can see either the input or output voltage (switch selectable), though those ones benefit from a piece of red acrylic over the display.

[Alien 13]

I use 4 of the DC-DC convertors in a box so have 4 independant outputs

2 x 7.4V for camera and video light (for day time use)

1 x 6V for my mount

1 x 5V for my mobile phone that is uses as a timer

The inputs can be 12V from a wall powered adaptor or 13.8V from a mobility scooter battery

Alan

[Guest]

For powering a canon camera you don't really need anything but the 7808 regulator, no resistors or capacitors just connect wires to the legs of the 7808 reg, as long as you use a regulated input power supply or a battery, with no real fluctuation of voltage.

But if you are going to draw more than 1amp (which the camera won't) then you would need the heatsink fixed to the regulator.

Makes it even easier

Olly