Step 1: Getting What You Need
The radio control and propulsion are from a toy Jetski. These are available in toy stores like KB-Toys. They sell for $19.00, and are easy to dismantle. I found two more in secondhand store toy bins, so don't be afraid to check there too. (E-Bay too) There are other toy boats that could be used, but I like the motors underneath. They allow for differential steering. Without a rudder, it becomes less complicated to rig a duck to steer. The motors run independently, both on for forward, left on to turn right, right on to turn left. It will rotate in place, so its easy to keep a baby duck in frame, and is quick enough to follow a family around the lake without their attention. The Jetski is from a company called Echo, and uses a radio frenquency of 27mhz. Range is a bit restricted, about 100 feet, but on a body of water thats pretty far. You could easily install a more powerful RC and electronic speed control, but costs will really run away if you do.
Last is a duck decoy, and you will need two. Males and females are available in nearly all species. I chose a Mallard male, and somtimes tow a female behind. They cost about $4.00 each, and are made by a company named Flambeau Products. They are available in sporting goods and hunting supply stores, online and mail order. They are a bit seasonal, but not too difficult to find. I purchased two for $3.99 ea. The reason for two, is the first is cut open with and oversized opening to cover the back of the second, to provide enough overlap that it becomes somewhat water resistant. This may seem a bit wasteful, but they are inexpensive, and its too important that you protect the camera from moisture.
The extra decoy makes a great planter, or use it as a pencil box on your desk or maybe a cereal bowl or even a dog dish!
Thats it! Simple tools are needed, a drill, and a Dremel tool is handy, a few connectors, and some NiCad batteries. (A broken hacksaw blade cuts the back easily if you don't have a Dremel.)
Step 2: Lets Get Started
Next is the back opening. This is difficult to explain, but you need a lid to place over the hole in the ducks back. I simlpy traced around the back of the first decoy with a pencil, kind of following the feathers and wings, to create an opening that is much larger than you need to get access to mount the components inside. Cut along this line carefully. You now have a hatch cover for your decoy.
This Hatch cover, is then placed onto the second decoy, trace around this hatch with pencil, and lift it off. Now trace about a half inch inside this line all the way around, then erase the first line. This marks an opening that is smaller than the cover. Cutting with the Dremel on a medium speed is safe and easy to control. I cut my first one with a broken hacksaw blade that I keep on my hobby bench, I just pierced the back with a pocket knife, pushed the hacksaw blade into the cut and followed the line around the back.
Step 3: The Jetski
Later, I sealed the hull bottom, and reassembled the empty, motorless jetski with a weight glued in the bottom. It's now a bathtub pushtoy for my grandaughter.
Step 4: Prepare the Camera
The camera and antenna are mounted to a base unit, that is also the case for the transmitter. Remove the screw on the back of the camera to release it from the adjustable arm. Removing the screws through the bottom of the base frees the transmitter from the case. Pry the paddle antenna from the transmitter case and cut the plastic to free the wire leading to the transmitter. Try not to let things dangle free, keep them supported to prevent the wires from flexing at their solder joints on the transmitter board and breaking free, Just treat it gently.
As a note, the camera can also be removed from its case to reduce its size significantly. It will fit into the head of a model airlpane 1/4 scale pilot.
For this project I left the camera in its case.
Step 5: Mount the Camera
Cut the side from an alluminum can, and roll it around a wood dowel to make a cigar shaped tube. It's inside needs to fit around the plastic camera lens. Make this while the camera is still outside the decoy. Use superglue along the long seam to hold the tubes shape. Once the camera is inserted into the decoy, slide the tube through the neck hole and over the lens cover. Secure the back of the camera with a tiewrap. Apply superglue around the tube along the neck opening to seal and hold the tube in place. When the glue dries, grind very gently around the edge of the tube right up to the neck. The edge can be finished with fine sandpaper if its still rough. Another coat of glue around the edge makes certain water stays out. I didn't glue the tube to the lens. It fits tight to the lens cover, and water will not get into the duck here.
The Decoys head is turned a bit to the side and the beak is out of the cameras view. If you choose a decoy with a different pose, you may have to position your camera a bit differently.
Step 6: Mount the Motors
Remove the rubber gasket from each of the motors and position them on the aluminum strip near the ends and over a ftat area. Be certain they are centered and aligned so the motors will be straight. Mark the holes onto the aluminum, and remove it and drill 3 1/8 inch holes. Place the strip back into the decoy and drill through the aluminum and the floor of the decoy.
Apply a bit of silicon to both sides of the gasket and place it onto the motor case. Lead the wires up through the bottom and the aluminum strip inside, and secure the motors with their original screws until tight. Wipe any excess silicon away.
*Note- I may have overcomplicated this step. You are simply drilling from inside the decoy and using the rubber gasket as a pattern to space the holes. Adding a reinforcement to this area is not as important as I make it sound, and the rubber gasket on the motor works well to keep the inside dry, as it did originally on the toy Jet ski. If you have sealant, and thin aluminum or plastic to strenghthen the bottom it can added, but shouldn't cause a problem if left out.
Step 7: Mount the Radio and Batteries
I built battery packs from NiCads that I had salvaged. The radio needs a nine volt power supply. A 8.4v RC car battery pack would also work.
The camera system needs 9v to 16v, and should have its own battery. I built a 12v NiCad battery that gives about 6-8 hours of video. The decoy spends most of its time on the water just floating and watching, and needs a heavy duty battery. A 12v Drill battery would work.
When mounted in a model airplane the camera simply uses a 9v alkaline battery, because flight times are less and the weight restrictions of an airplane.
Once you build or purchase your battery packs, place them in the center of the decoy on the foam and trace around them with felt pen. Cut out this area with a hot soldering pencil or hacksaw blade so the packs fit tightly into the foam. They should be resting on the floor of the decoy to keep the center of gravity low. Then cut-out an area for the radio at the rear. Position it so the wires for the off/on switch and antenna reach where you plan to mount them. I placed them on each side of the tail, near the top and outside the outline of the hatch. I mounted wood dowels in the foam but never screwed the radio receiver to them, a tight fit is all you need to hold everything.
Lastly here, the connections to the batteries need matching connections to their systems and their chargers. Buy two female connectors and four male connectors. I use wall wart chargers. A 12vdc 50mA for the camera battery and a 9vdc 50mA for the radio battery. Solder a male connector to the chargers, and female connectors to the batteries. Then solder male connectors to the radio and camera power leads. This all makes sense later when you simply open the back shell, unhook the batteries and connect the chargers. An overnight charge and your ready for a day on the water.
Radio Shack, and department stores have wall chargers, and don't forget second hand stores, they all have piles of them to look through. Both of mine came from old cordless phones I had saved for parts. Just match the polarity and the voltage to your batteries output and don't exceed 50mA so you get a long gentle charge rate.
Step 8: Finish and Play
The last bit of construction is to add a switch to turn the camera system off/on. I had a second doner jetski that came from a second hand store toy bin so my camera switch matches the radio switch on the back of the duck. A suitable switch from radio shack or a auto or marine store could be used. Mount it near the head, high up so it stays dry and wire it between the video transmitters negative wire and the connector to the battery.
The hatch is placed over the opening and held with tape. Drill 4 to 6 holes around the edge through the cover and the sides of the decoy with a 1/16th drill bit. Don't go too deep. Use the screws from the jetski deck/hull and drive them through the hatch. remove the tape and admire your new toy! Congradulations!
When removing the hatch, only remove the screws about half way and pull up on the sides while turning the screws. The hatch will come off and the screws will still be attached to the lid. No loose screws to keep track of, and maintenance is a snap.
The inside stays dry, but after a day on the water I recomend removing the back to let it air dry. Don't turn it upside down, if there was any water inside you'll want to keep it away from the video transmitter in the head. Keep your batteries charged when not in use, and they'll last for years.
If they ever market one of these, I'll guarantee it would run about $450.00. You now have one and didn't have to wait! Pays to be a nerd, be resourceful, and visit the instructables website regularly!
Have fun and enjoy your creation, I will!
As a final note, let me add that this should only be used for fun. Never take a motorized decoy hunting without checking your local regulations. I am not responsible for any missuse or malice caused by others. Please, consider peoples privacy, and only video if it's proper to do so. A hidden camera can cause some to be concerned. How you operate the camera can become a legal issue. Protect yourself by avoiding even the slightest appearence of misconduct, and if in doubt, turn it off and put it away.