I want to be able to fly my drone without relying on satellites. A phased array radar would allow me to track and guide my drone. But, they are expensive. So, I decided to design my own, using inexpensive, off the shelf components. The basis of the system is Efratom's LPRO Rubidium Frequency Standard. It is the first atomic frequency standard designed to be mass produced and it has a 10-20 year life. They are commonly available on…See More