Pictured opposite is the Bridge Radar. Compared to modern day systems this system can at best be described as primitive - but at the time of the Freyr build it was yet another feature of the Freyr (Ross Revenge) that was yet again ahead of its time.
The origins of radar go back to 1842 when Austrian physicist and astronomer, Christian Andreas Doppler, wrote a poper on determining motion, using the frequency of light in his study of the movement of stars.
His discovery in 1842, most commonly known as the Doppler principle, was based around the concept of assessing how radar determines speed. Of course in 1842 there were no radars but Dopplers' discoveries were many years later to be the foundation for radar development.
During the 1930's scientists discovered that when a ship passed between radio transmitters some of the signals reflected back to the source. A team led by Sir Robert Alexender Watson-Watt developed the first usable ship based radar in 1935, utilising this discovery in conjunction with Doppler;s principles.
Christian Andreas Doppler
Sir Robert Alexander Watson-Watt