7 mhz quadrifilar

7 mhz quadrifilar

Antennas : 70cm

• Quadrifilar Helix antenna for 436 MHz - This is an antenna that author just built. Was intend for receiving the AO-27 downlink (at 436.800 +/- doppler). It is built with right hand circular polarization, and the gain is supposed to be in the neighborhood of 3 DB.
  [ Hits: 3896 | Votes: 4 | Rating: 4.5 ]

• 137 MHz QHF Quadrifilar APT Antenna - This version of the 135MHz quadrifilar antenna for APT reception is an adaptation from Bill Sykes and Bob Cobey's article Taming the QFH which appeared in the March 1997 RIG magazine.
  [ Hits: 6758 | Votes: 34 | Rating: 4.95 ]
• Helix Antenna for 137 MHz - A Quadrifilar Helix Antenna for 137 MHz By George Goodroe, KF4CPJ
  [ Hits: 2174 | Votes: 6 | Rating: 4.5 ]
• 137MHz Quadrifilar Antenna - This version of the 137MHz quadrifilar antenna for APT reception is an adaptation from Bill Sykes and Bob Cobey Taming the QFH which appeared in the March 1997 RIG magazine. This article contains detailed 3D pictures and models and detailed pictures.
  [ Hits: 232 | Votes: 3 | Rating: 7 ]