Old camera and a transmitter bought from www.northcountryradio.com
Wing Cam - Live video from a Flying Wing.
Remember to visit our model airplane club, called SKM. Find their "Landing field" on the web at www.skm-rc.dk.
Now that we have these wonderful flying wings, which fly amongst the birds in the sky, why not make it possible to se what the birds se when they fly in the sky!!
Why not mount a camera on the wing and transmit live video directly from the wing to the ground, where I would sit with my screen looking "down" on all the little people on the ground. I have been looking several places on the internet for stings that could do the trick, and found a cheep -yet efficient method of transmitting the video signal to the ground.
First I bought a ATV transmitter kit from www.northcountryradio.com which emitted directly on 439.25 MHz (receive the signal directly on TV!!!) with 1 W. I used a B/W camera that I had bought a long time ago, but all of this used over 350mA at 12 V, which was way out of my scope. I never tested this equipment on a plane, because I simply could not believe that this was the way to do it - there had to be a simpler and more efficient way.
Old camera and a transmitter bought from www.northcountryradio.com
On several sites I found the link www.x10.com and how the products were used. The equipment is sold as wireless home surveillance equipment, but with easy alterations it will be capable of traveling amongst the birds in the sky.
I must admit that my deal was somewhat other than usual, because I got a used set, without the casing but this is not something that I planed on using anyway.
Links to other cam-on-plane sites
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Hacking the Equipment:
I dismantled the antenna (for curiosity reasons) and soldered the wires of. The antenna provided with the equipment is not ok, since the transmitter is directional, and the receivers antenna is not optimal for this job, so both are dispensable. (but remember to save the coaxial cables, since these are are used later in the project).
The Transmitter:
To be able to fit the transmitter in any model, and not break off the wires and damage the PCB, I made a small box for it. It was made from old thin shield plate from old VCRs/ TVs etc:
Finding the right plates (without adjustment holes).
Cutting them out: Top And bottom are 46 x 46 mm / All sides are 46 x 15 mm
This way the PCB fits perfectly inside (remember to place a isolating plate of
some sort, in the bottom and top of the box, to make sure not to ruin anything).
First solder the Sides on to the bottom.
After fitting the PCB, solder the top of the box. Only solder the corners, since you want to
be able to get in there again some
time!!!
The Transmitting Antenna:
For some better performance (Distance) of the transmitting signal, it is best to have a Dipol antenna or GP (or just a omni directional antenna), that has a propagation pattern similar to a doughnut.
Most of the signal will be transmitting out the side of the plane, which is mostly what we want!
The antenna can be made in several ways: I first made a dipole as described on the RC-CAM page, but this construction has a flaw, that is that the inner core might break in the joint (and you can only find out by removing 2 layers of heat shrink). This happens if the antenna is bend to much (to many times), and that was what I experienced on test flight - for hoping to increase the performance of the antenna, i placed it on the underside of the plane, which I used to land on!!! - Don't do that.
Dipole in double heat shrink under the wing.
So I thought of making a god old GP antenna, with the casing of the transmitter itself as part of the antenna (They are so great when they are so small).
The final result looks like this:
- And do I need to say that the result was much better that first test - Even
better than expected.
This is how I build it:
Cut 5 pieces of thick wire in 3 cm length, and solder the four pieces so they form a pyramid like shape.
Solder the outer shield of the coax cable to the top of the pyramid, with the inner wire exposed and pointing to the skies.
Solder the last 3cm piece to the inner core of the coax cable.
Check that the distance from where the shielding ends on the coax cable and the end of the wire is exactly 3 cm - Adjust if necessary.
Take a stick of this heat glue (from Bostick glue guns) and cut in 2 pieces that are 1 cm long.
Cut these 2 in halves, so they form 4 half circles 1 cm long.
Heat the center of them with a soldering iron till the center is fluid, and place it directly where you have the top of the pyramid, and the beginning of the topmost antenna wire. And do this on the other side with a new piece.
The last 2 pieces are placed on top of the other two, to form a firm support for the Ground Plane Antenna feed point.
Observe the result of the glue used in step 5 - 8.
The Receiver:
The receiver is dismantled and besides removing the existing
antenna, an external BNC is fitted to use on a much larger and signal amplifying
antenna.
This will also help to be more experimental when finding new antenna designs.
The Receiving Antenna:
I forgot to take pictures during the process, but I will try to describe how I did the construction. Building this antenna can be done in many ways, and the result and choice of materials is mainly determined by what's in stock (what's in the shed or commonly available).
I might consider making a YAGI-UDA 
to se if t is a better choice.
Materials:
One Ø = 40 mm (outer dimension) plastic pluming tube bought in local warehouse for 50,- DKR for 1 Meter.
Aluminium plate.
Some meters of 1 mm single threaded stripped wire.
Some 1cm thick Plexiglas or plastic (explanation se below).
A antenna connector of your choice.
I used the following formulas to make the antenna:
Taken from the best and the biggest 
(The ARRL Antenna Book - ISBN: 0-87259-206-5)
Or you can download the antenna.xls file and find the dimensions needed, and even alter them to fit your own requirements.
The construction was as follows:
The antenna base:
"X" marks the center of the tube and the Aluminium plate.
The tube:
Observe the cut in the tube to solder the antenna wire on the antenna connector
Now its time for the antenna impedance matching:
And see image above.
Now you are more or less done. The last part shouldt have been done with a proper measuring equipment, but I am not so lucky to have such a monster in my closet.
Equipment in use.
Testing its possibilities.
This is some grabbed stills from second flight, They are OK, But the grabber is NOT optimal (200,- DKR - Using the Printer port).
Ups - No connection
I also have some AVIs but they would quickly fill up this web site!
These are pictures of the equipment mounted on the flying wing.
Observe that I placed an extra Servo to be able to tilt the camera up and down.
This made the view adjusting much easier.
When I land the plane, I point the camera up, to prevent dirt ant other
particles to damage the camera lens.
Desperately seeking a monitor
What I am desperately missing, is some kind of monitor that will enable me to view the live video, directly on a screen. The video grabber is really a last solution, because no other way was found.
The requirements for the monitor/viewing device is:
Run on 12 Volt.
PAL standard composite video signal direct input.
Color.
Transportable
Preferable a LCD - TFT monitor - used in cars, real airplanes etc. But I have also been looking for a scrap video camera, where the viewfinder would work, and I just needed to remove the viewfinder and mount it on a helmet or a pair of glasses. This would be permanently fitted on my right eye, to give a birds view. - But video cameras seem to disappear into thin air when they break. I haven tried almost every service shop, and they don't have anything for scrap!!!
Please.... if you have one for the waste basket, please throw it MY way.
Remember to visit our model airplane club, called SKM. Find their "Landing field" on the web at www.skm-rc.dk.
Any questions or comments. Please feel free to contact me.
Email me at - kimfmx@gmail.com