How to Make Your Own Night Vision Goggles for Under 50 Part One
First and foremost I should say that you get what you put in, meaning if you buy a product you get what you pay for, when making something the more hard work you put into it the better it will be. First the following is what you need to make a working night-vision goggle.(If you read my other night-vision article this will be a commercial infrared and low-light night-vision.) If the rest of this paragraph gets more technical than you care about skip to the list of needed materials. Upon further research I believe this Night-vision goggle is actually near-infrared. This means the LEDs used are near infrared not pure infrared, this discovery explains why the LEDs give off a red glow. Also they are more effective because the camera can see the near infrared light but infrared is right on the edge of what the camera can see, making the LEDs invisible in the dark but they don't offer much range in night-vision.
- At least 10, 200 mW 10 millimeter triple chip infrared LEDs in the 850nm range (as long as they're 200mW you can use smaller ones if you want, we will be using ten in this project). I also recommend you get the holders of the corresponding size, they make it easier to hold the LEDs in place without tape.
- "Hobby Box" which can be purchased from Radio shack, you'll need one at least 6" x 4" x 2", if this will be your first project I recommend you try to get one a little bigger.
- Also from Radio shack, you'll need 10 Ohm resisters (sold in five packs, one pack is good).
- Two 9-volt batteries
- One or two simple switches, the linked example are excellent because they come with plenty of extra wire that you can use else where in the project.
- Micro pinhole camera, like this one. If you can find another one for a better price that's great but that's what your looking for.(you don't need one with audio, try requesting one from this person)
- A soldering gun/iron and solder, they can be found at most hardware stores, and you can ask at radio shack since you'll be there to get the other items anyway.
- A multi-volt meter
- Finally, you will need an old analog viewfinder. These can be found on e-bay, but I really don't recommend e-bay for this item. I used a viewfinder from an old RCA camcorder we used to use, with no microphone built-into the viewfinder. If you can find an old viewfinder, in your garage, in a garage sale,etc. find out how many individual wires go into it (requires taking it apart), you'll want three, four at most (unless your experienced with electronics and are confident in your ability to determine the purpose of all wires, some viewfinders have eleven (11) wires.) If you can't determine which wires are which than you need the camera as well. Note: If you know how to distinguish wires please write a comment, factoid, private message to me,etc.
- A clear place to work and solder, if possible have some alligator clips (or similar) available to hold wires while soldering, it is possible without clamps, but is more difficult.
- Pen/pencil and a few pieces of scratch paper.
- One or two extra 9-volt battery hook-ups, get at Radio shack (these are the things that are used with 9-volt batteries, with something that uses 9-volt batteries in the battery compartment there is a small plastic or rubber tab with the unique 9-volt battery hook-ups)
- Electrical tape, screwdriver, wire cutters, extra wire (if needed), wire strippers (if you happen to have them, but the cutters can be used if your careful), and a knife. Use the tools as you see fit. Any other tools that you need to cut, drill, and smooth plastic.
Finally it is time to begin, before wasting time and money getting the other parts, find a viewfinder. Once you have one as described above find where the wires are soldered to the circuit board, once you know it has the right number of wires you will want to carefully remove some of the rubber cable around the wires (not the wires' insulation, the rubber keeping the wires in one cable). Stop before you remove the part that plugs into the camera. Before plugging the viewfinder into the camera, set the volt-meter to Ohms (consult the manual) and touch electrodes of the meter to the exposed solder at the end of the wires. Systematically test all the wires going into the viewfinder, if the view finder has four wires, one wire will always give you a resistance of one. This one wire is not the video, negative, or positive wire, write down the color of the wire that always has a resistance of one. Plug the viewfinder into the camera. You'll NEED to be careful not to have it resting on a conductive surface and don't touch the inside with your bare hands (I take no responsibility for you being stupid or careless, that goes for the soldering portions as well). With the view finder powered on with an image on the screen, take the volt-meter (set to measure volts, adjust sensitivity as needed) and touch the exposed solder like before to figure out which of the remaining wires is which, but don't touch the wire which color you wrote down as having a resistance of one (probably won't hurt anything, but better safe than sorry).
Determining the Three main wires
If you assign the wires numbers, for this we'll say number 4 is on one end and is the one resistance wire, if you touch wire 1 with the volt meter electrode and wire 2 with the other make note of the reading (a chart with all possible combinations could be helpful) it doesn't need to be accurate on the number, or even stable, but you need to know whether it is positive or negative. Do this with the remaining wires.
On most volt-meters the red electrode is positive (touch the red to the positive terminal on a battery and the black to the negative and get a positive reading). If you touch wires 1 with the red and 3 with the black and get a negative reading than 3 may be the positive wire. When you are testing wires, if the the screen flickers one of those wires is the video. Simply being systematic will allow you to determine the Positive, the negative and the video. Once determined write them down using either the color or the numbers you assigned them.
When you are certain of the wires functions you may unplug the view finder and cut off the plug going to the camera with wire cutters, cut as close to the plug as possible, you want as much extra wire attached to the circuit board as you can get.
NOTE: This was written with knowledge gathered from only two different RCA viewfinders, this guide will work for that type and only may work for others, good luck.
Now you need to double check the polarity of the 9-volt battery hook-up wires, they should be standardized but to be sure they should be checked. plug in a fresh 9-volt battery and touch test the wires using the volt-meter, remember red is positive. So if you touch the red terminal to the red wire and black to black, but get a negative reading then the terminals on the hook-up is reversed, be sure to note this.
In part two I will cover the rest of the process, in comparison to finding the right viewfinder the rest is pretty easy.