Montana Ghost Hunter

So this was a fun project. Our paranormal group was looking for a way to get some more IR light for or our static video cameras and/or for our rooms that could use a bit more for the hand held cameras. We were trying to determine what would be more cost effective.. buying illuminators or building our own. I already played with converting a flashlight using gels with good success, but I wanted to give IR LEDs a shot.

Searching the internet I found a few IR kits, and settled on a kit with 36-850nm LEDs providing a viewing angle of 50 degrees.

I’m a nerd by nature, so the idea of soldering a bunch of LEDs to a circuit board.. is fun!

One of the challenges I wanted to overcome was having some flexibility for power. This IR kit requires 12 volts to power it. I wanted to be able to power this via batteries OR by plugging in a 12V DC adapter.  I wanted it to do both so it can handle various scenarios and situations.

I did some reading on how to achieve 12 volts with batteries and decided to go with 8 AA batteries wired in series (not parallel). Each AA battery has 1.5 volts, so 1.5 * 8 = 12. Since the plan was to put this in a piece of PVC, I went with 2 battery holders holding 4 AAs a piece.

Wiring them in series means to connect the + and – alternating between all the batteries. I did some testing with a volt meter and alligator clips.

After soldering the LEDs and resistors to the circuit board, I wanted to give it a quick test with my battery packs. I wired some leads off of the board and hooked everything up with alligator clips.

The next challenge is to figure out how to control the power source. I opted to use a DPDT (Double Pole Double Throw) toggle switch. You could also look for a On/Off/On toggle. Basically, if the toggle is pulled to one direction it will use the batteries. If the toggle is pulled the other direction, it’ll use the external power. If the switch is in the middle configuration, the unit is ‘off’. I used a GC (35-012) On-Off-On miniature bat handle toggle that I had laying around.

I also bought a DC power jack. Make sure you know what your inside diameter (ID) and outside diameter (OD) of your plug. I picked up one from radio shack (274-1576) which was 5.5mm OD x 2.5mm ID.

The housing is a KBI PCV coupling. I think I paid $6 for it. It has a 2″ opening, which I had to use the dremel to get it a hair bigger to accept the circuit board. I measured the 12V DC jack and toggle, and drilled holes for those. After drilling the holes, it was time to wire everything up. It’s important to pay attention to your polarity and to test prior to soldering. I love my alligator clips!

Once you have everything wired up and tested, put everything into the unit. I had to get a extension cap for the rear since the batteries were longer. I think the next one I build, I’ll get a better housing for it. Ace had a limited selection, so I got the best thing I could.

Here is a side view showing the cap and toggle switch.

Here is another side view showing the 12V DC jack.

This was a fun project, and I’m looking for the next one I build. I think for the next one, I’ll add some type of tripod assembly or mounting hardware.