After hearing of Bruce Simpson’s planned FPV Diversity Controller project I thought I will do my own DIY diversity controller based on his project. If you’re interested please give Bruce a visit on YouTube or his website.
Why my own diversity controller?
Well first of all I like building electronic circuits and I love to play around with DIY projects. Unfortunately just building Bruce’s original circuit would not be possible for me. The reason is that he uses a PIC micro controller for his project. I do not own a PIC progrmming device. But what I own is an Arduino and a bit of imagination…
At the time I started this project in January 2014 Bruce did not yet have released his diversity controller so I started to work on the software and the basic circuit on a breadboard. As soon as Bruce’s version of the DIY controller will be release I’ll try to integrate my work into his circuit as I don’t have enough knowledge about how to build the video output buffers.
Luckily Bruce said his whole project will be open-source. So it will be possible for me to incorporate some of his knowledge into my own project. Of course everything I do will also be available of free under the GNU GPL open-source license.
The heart of every diversity controller is of course the micro controller that does the actual work of deciding which receiver has the best signal and switching between them. The Arduino platform comes in very handy because it is easy to use and has all the tools freely available. Besides that you can get an Arduino super cheap for $10 from ebay.
So while the Arduino allows me to easily prototype and develop the software and the circuit, for a finished product you want something smaller than a big Arduino board. So I came up with the idea to use an Atmel ATtiny micro controller for the finished diversity controller board.
Why Atmel ATtiny?
The reason I chose an Atmel ATtiny chip for the finished product is very easy. First of all these chips are very cheap and easily available. But second, and more important, you can use an Arduino do program and ATtiny chip. So the exact same software that runs on my Arduino during the development can be uploaded to an ATtiny chip without any changes and even without the need for a programming device. You simply connect your Arduino with a few cables to the ATtiny chip. And with the push of a button in the Arduino IDE the program will be uploaded to the ATtiny chip instead of the Arduino. After that the ATtiny is capable of running on it’s own. So no more need for the Arduino in the finished circuit.
Visit www.bitbucket.org/rgruber/fpv-diversity for all resources of this project. You can find the source code, diagrams and photos there.