vertical antenna tests sans coil

[last updated: 2024-05-26]
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coil-loaded vertical antenna experiment:
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• Initial setup:
  • telescoping, 5.6m antenna as noted before
  • placed antenna, mounted on tripod, in middle of yard, away from trees and structures (20' or so anyway)
  • feeding with 100' of 8x cable (AFAIR)
  • radials: 2@ about 10' long stretched on on the ground about 60deg apart
  • ferrite clamp bead around 2 loops (three strands through clamp)
  • reading SWR on CH0 on nanoVNA

  • Calibration tests:
    • calibrated nanoVNA at antenna-end of feedline
      14 MHz to 30 MHz
      saved to C0
      full length:
      SWR 4.5 at 14.0 MHz
      SWR 5.6 at 14.32 MHz

      SWR 28.5 at 28.08 MHz
      SWR 26.3 at 29.04 MHz

      
      shortened by two sections:
      SWR 1.32 at 14.0 MHz
      SWR 1.8 at 14.32 MHz

      SWR 18.3 at 28.08 MHz
      SWR 19.5 at 29.04 MHz

    • calibrated at nano-end of feedline:
      saved as C1
      full length:
      SWR ... at 14.0 MHz
      SWR 1...at 14.32 MHz

      SWR .... at 28.08 MHz
      SWR .... at 29.04 MHz

      
      shortened by two sections:
      SWR 1.24 at 14.0 MHz
      SWR 1.55 at 14.32 MHz

      SWR 4.46 at 28.08 MHz
      SWR 4.46 at 29.04 MHz