Jump to content
Scruit

Automatic camera selector

Recommended Posts

I would like to have two cameras attached to the same channel on my DVR, and I'd like for the system to automatically switch between the two channels.

 

The scenario is the rear-facing camera on my dashcam setup. For the thrid time now, while the car was being worked on at a dealership a tech was examining the camera system that is behind a false panel in my trunk. The rear-facing camera is mounted to the towbar. All I caught was their ankles and they were discussing how the system worked and wondering if I was a hidden camera TV show or something. This got me thinking about if someone breaks into my trunk - the camera system will turn on automatically but I'll only catch their feet from the towbar mounted camera. It'd be great to get a face shot (bearing in mind I still have to deal with dark subject/light background etc).

 

So, I'd like to install a second camera inside the trunk that would see someone who enters the trunk. I'd like the trunk cam and towbar cam to share the same channel on the DVR. Normally I want the towbar cam to be active, but when the trunk opens I want the trunk cam to be active instead.

 

Here's a simple circuit I was thinking of:

 

97943_1.gif

 

I know this might make the DVR see a VLOSS as the cam switches over, but I can live with that.

 

So, would this work? Would it blow my DVR up?

Share this post


Link to post
Share on other sites

Good idea. The DVR should be ok as long as you only have 1 feed at a time going into the port. I'd be more concerned with sending 1 video feed into another camera. I don't know if it's damaging or not, but it would be better if you could switch the video too.

Share this post


Link to post
Share on other sites
There are a few options - you could use a Camera Sequential Switch, like the Pelco VSS5000 series Capable of Operating on 12 VDC for use in Mobile Applications

 

Or you could use a Quad with a built-in sequencer, like the ARM CQ41 or CQ42 http://www.armelectronics.com/page.aspx?p=42

 

Both have alarm inputs that could be triggered by a microswitch.

 

I had looked at these and see that they seem to run a couple hundred dollars each. I was hoping for the simpler solution. I'll give it a shot with some old throwaway cameras and a 7" lcd screen I've not used in a while. If I wreck something then... meh...

Share this post


Link to post
Share on other sites

I have two 15W sirens attached to my DVR housing. They will only open it once and there is no way of silencing it unless they call me.

Share this post


Link to post
Share on other sites

Hey Scruit, you could do this easily with an "ice cube" relay that has a 12vdc coil. You could use the trunk switch (which normally turns on a light) to also activate the coil of the relay. Just have the positive (+DC) go into the "common" side of one of the contact points. Use the "normally open" set of contacts to fire the trunk cam. When the trunk opens, the relay coil would fire, then close the N.O. set, away from the N.C. set, which would then open . I do this exact same sort of setup, I just have a photocell which controls the "ice cube" relay, in order to switch between B/W and Color cams.

Share this post


Link to post
Share on other sites

that's a really bad way of switching the cameras -it will work tho.

A better way is to have the cameras powered up and switch the video.

via a relay etc. [sPST $5 at any electronics store]

 

but remember if they break into your car they might leave the trunk open

which will be no good when there in the front. A small microwave motion

detector in the trunk would fix this. [hooked to your video switch relay]

 

z

Share this post


Link to post
Share on other sites

I'll give it a shot today. I'm changing the circuit do that the relay switches the center wire of the coax instead of the power. Both cameras would be powered up up all the time and the ground (the outer braiding of the coax) for the two inputs and the one output will be connected together.

 

If this works out then I have a few different places I could use this.

Share this post


Link to post
Share on other sites

Finally got it put together. It's a very simple circuit, just lie the diagram above only it switches the center connector of the coax instead of the + wire of the power.

 

It works great. I'll have to use this in other places too... Maybe my front-port camera can swtich to a close-up face image based upon a motion sensor... Hmmm...

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×