Portable Power Help

[Mattjohnson1978]

Hi everyone!

I am looking to make a portable power box for my mount/camera/laptop etc but would welcome comments from anyone that has had experience in this.

I intend on using the biggest leisure battery I can find to help with all the loadings but I have a few concerns. I have read somewhere that running a mount and camera from the same power source can cause issues but not sure if this is true. I have an NEQ6 pro mount and Canon 550D camera. I can't see how it could cause problems but then there may be forces that I don't understand!

I have sourced a suitable 12v power converter for my laptop, and my mount is 12v anyway but with regards to the camera supply, has anyone got a circuit schematic that shows a working conversion from 12v to 7.4vdc? I already have the dummy battery for my camera so just need the power converter. I have an electronics guy on standby to make me one and would rather not spend £40-50 if I absolutely didn't have to. Again, any comments or experiences would be very welcome.

All my imaging has been done from my garden in the middle of a city and would love to get out in those dark skies sooooon!!

Thank you in advance for any input

Matt

[Horwig]

Hi Matt, some thoughts on a power pack. Firstly the 12 to 7.4 volt converter. I'm using an LM317 voltage regulator to power an Eos 450d, dead easy circuit, only needs two resistors and two capacitors, all available from Maplin amongst others.

Here's a link to an article which explains the circuit:

http://integrated-th...pply-using.html

I built mine into an old battery, works fine, doesn't seem to cause any heat problems in the camera.

I run all my setup from a 12v bench supply, mount, camera and dew heaters, and have never had problems with interference between mount and camera. A well charged battery should be equally good, but if it badly discharges, it would be possible in theory to get voltage dips when the mount takes current, these might cause noise on the supply which could upset the camera. The filter capacitor on the input to the regulator should help cope with any noise on the supply caused by the mount or dew heaters. (If you look closely at my circuit board you'll notice that I didn't even bother to include one, and it still worked!)

Huw

[Mattjohnson1978]

That is exactly what I need, thanks Huw!

I'll probably mount the PCB in a box as the dummy battery I have is also the mains supply. I'm going to plug/socket the lead that goes to the camera so I can switch it for both uses. I plan for all of it to sit inside a heavy duty crate so the lot sits under mount......will be watching the weight tho!

Thanks again