Rear View Video
I recently rigged an inexpensive rear view video system for my truck and trailer using an X-10 video camera and receiver connected to a flat screen monitor. An amateur radio friend, John, K7OSK showed up at a swap meet with an X-10 setup on his 5th wheel Alpenlite, and once I saw it, I had to have one.
A major problem when pulling a trailer is the blind spot in back. People can sneak into the blind spot and camp there for miles without you knowing that they are there, and it makes backing a real problem. I would never use my video setup for backing since it does not show the corners of the trailer and the viewing field is limited, but it is very useful for making sure that the area is clear as you back.
The big problem with duplicating this setup would be in finding a flat screen monitor that operates on 12 volts. John used an inexpensive TV with RCA jack video input for his monitor and it works well. I like the flat screen because it is smaller. I had one on the shelf at home that I had picked up at a swapmeet somewhere and it was ideal for the purpose. I had long wanted to mount it in the truck, but did not have a good place for it. John came to the rescue on this one - he mounted his monitor behind the driver's seat so you can watch it via the rear view mirror. This gives you the same perspective as looking out the back with a mirror (left and right are the same as in the mirror) which helps a lot. My little monitor is only about 5" diagonally, and the effective viewing distance is about six feet, so you cannot see a lot of detail.
I ordered a color "Camera Kit 203CA" from a mail order house that no longer seems to be in business for about $40. You can search the name and model number on the web and find lots of them. If you don't have any luck, try "X-1- video" and you will find it. My kit consists of a tiny (about the size of a stack of ten quarters) color camera, a battery adapter and a video receiver with RCA output. My camera mount is extremely simple. I used shears to cut a piece of soft sheet aluminum to approximately 1 1/2" X 3 " and drilled a hole near one end for the camera lens to look through. I used hot glue to secure the camera to the mount and then drilled a 1/8" hole in the other end of the mount and screwed it into an existing hole in the back window frame so it looks out the back window.
The monitor and receiver mount was a little more complicated. See the photos:
I built a plate to mount the receiver (the black box under the monitor) and monitor and then brazed two steel rods to it. These rods fit into the headrest holes in the center of the back seat of my extra-cab Toyota Tundra.
I tested it out on the road and it worked OK, but only OK. I greatly improved the video picture by straightening the transmitter antenna (a little piece of wire) and making sure that it was vertical like the receiver antenna. The distance between the transmitter and the receiver is only about 20 feet, but the metal of the truck and trailer degrade it a lot. The picture varies considerably with conditions. The direction of the light hitting the back window, ambient light conditions, rain on the window and proximity to dense objects all effect the picture. When you are in open country the picture is excellent, but if you are in a congested area or driving down a narrow road with lots of trees or rock on the sides the image will flicker because of reflected signals. In any case, the is good enough to let you know if something is back there.
The camera came equipped with an adapter for a standard 9 volt radio battery, and I quickly discovered that the battery life is limited. I bought a cheap DC transformer that plugs into a cigarette lighter jack and wired it up for the transmitter. Fortunately I had a cigarette lighter socket handy in the trailer. I learned the hard way to use some not glue to secure the polarity switch on the transformer. The transmitter has no reverse polarity protection, and I fried a transmitter when the switch was accidentally moved when inserting it into the jack.