If you get a Beetle quadcopter and have a video transmitter laying around in your house you might consider doing this.
NOTE: I used a CNC to mill out the parts but you can as easily do this by hand.
Parts you need:
1. Beetle quadcopter
2. Video transmitter 1.2GHz (in this example) but the camera has to be of the lightweight type. I used a camera with built in RF transmitter.
3. Step up converter from 3.7V to 9 or 12V depending on your camera type. I use the same battery for the quad and the camera link.
4. Monitor AV. I used a DVD player NextBase that got 10" size screen. The bigger the better.
5. Clover leaf antenna for the receiver. Look at http://rcexplorer.se/diy/2011/08/the-cloverleaf-fpv-antenna/ fro instructions. This step is a must if you have low signal output like 10mW. You can use a more powerful transmitter but it also requires more battery and the Beetle is a very lightweight vehicle. This setup weights 100g in total.
I added a photo of the receiver with the antenna for 1.2GHz. It is the bigger antenna. I also built an antenna for the 2.4GHz, channel 2 for RC transmitter and video link (smaller antenna). Remember, that lower frequency have better penetration. Using 5.8GHz is cool but you need more power for the same range. Lower band radio frequencies transmit through building materials easier than higher band frequencies. Unfortunately, lower frequencies are all occupied and reserved for other stuff. I would like to have a video link system on the 400-900MHz band which means affordable HD quality video. I am afraid that higher frequencies band like the 5.8 will inhibit HD quality FPV for RC amateurs permanently.
NB: the § § thingies are earrings for my girlfriend. Guess her occupation!
Price estimate USD:
Videolink: 20-25 (1.2 GHz)
Step up DC-DC converter: 2.5
JR connectors: 1
work for free :-)
monitor used DVD player free! But you can buy used similar to 20-40 $.
Total: ~$60 ($100 with used monitor)
Compare this with the Shark system.
Future ideas for development.
Buy a high resolution camera with 600 or 700 TVL for $20.