Now slide the Detector along its slot. It should be possible to observe very sharp drops (minima) in the meter reading. The reason is that, since there is nothing to absorb the incident energy, it is, all (very nearly) reflected back. THe reflected wave will therefore now almost exactly cancel the incident wave at places where their phases are opposite. Record, in a table headed 'Large VSWR' the maximum and minimum meter readings, and the scale position at which they occur. Plot a graph of meter reading against position.