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Test Hats & Hoods

Haigh-Farr Test Hats enable communication while containing the RF energy from an antenna.
Test Hat

Test Hats & Hoods

Haigh-Farr test hats provide a tight EMI seal, minimizing RF leakage, typically to -80 dB or lower. We construct our test hats out of a solid aluminum, one-piece case with a conductive EMI gasket where the hat is in contact with the ground plane and the antenna. The coupling factor is a design parameter; however, it ranges from 4 dB to 30 dB, with each hat calibrated. Haigh-Farr hats are designed to work with single or multiband Flexislot™ and Patch antennas, as well as single or multi-channel Wraparound™ antennas.

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  • Tight EMI Seal; leakage typically -80 dB or lower
  • Frequencies from UHF to x-Band
  • Single or multi-band designs
  • Precision fit enables repeatable electrical characteristics when mating/demating
  • Secure fastening. Flange designed to naturally mate to cylindrical, conical and other curved surfaces
  • SMA, TNC, and other connector options available
  • Low outgassing materials utilized


  • Contain RF Energy
  • Ground and lab testing
  • Reduced EMI environments
  • System verification
  • Late stage testing and last minute removal prior to flight

Power Dividers, Combiners, Hybrids & Diplexers