Mode-C tracking using PlanePlotter BeamFiner Plus is only available to users of the Mode-S Beast
For further information about the Beast , follow this link
U2 departing the UK tracked using Mode C BeamFinder Plus
Labels indicate Radar Head Pulse Rates
U2 tracked using Mode - C Beamfinder Plus and confirmed visually over the UK
Mode-S and Mode A/C Beamfinding
Demonstration showing how BeamFinder works using both Mode-S [ BeamFinder ... red ] and Mode A/C [BeamFinder Plus ... green ]
Location by radar pulse rate
In the above example the target a/c is sending no location data or indeed Mode-S.
It is however Mode A/C active.
Location is achieved by triangulation based upon the radar pulse rate of known radar sites combined with the squawk code transmitted by the a/c.
The aircraft invovled is a U2 climbing to FL600 on the way back to the USA
U2 departs Fairford climbing to 60,000 feet
Typhoon test flight 07.10.2011
Incoming U2 located by Mode C beams