From RadioNerds
Jump to navigation Jump to search

As part of the AN/MPQ-4(A) Radar Set the directional coupler CU-399/MPQ-4 is a special section of waveguide with a frequency range of 15,700 to 16,300 megaHertz. It is bidirectional with a nominal attenuation of 20 decibels (20db) and is used to sample the RF energy into in the main waveguide. This RF energy is fed into the echo box FR-111/MPQ-4A through a connecting section of waveguide.