To compliment our standard radio training, we also offer High Frequency Base Station Installation training, below are examples of this course


  1. Enable participants to gain an understanding of the requirements and practical considerations for installing a base station HF system


    1. To understand the basics of
      • A fixed base station
      • The propagation direction of an antenna
      • Antenna take-off angles
      • Antenna mounting height and effects of frequency change
      • Installing an antenna and site selection
      • Antenna earthing

Antenna testing

A fixed base station consists of:

  • Transceiver
  • Antenna
  • Power Supply

Topics covered include:

  1. Installation of a fixed antenna
  2. Installation of a transceiver
  3. Testing the base station installations

Proper setup of the system ensures the quality of communication!

Important facors to consider when setting up an antenna:

  1. Propagation direction
  2. Distance of communication
  3. Grounding
  4. Antenna support structure
  5. Antenna site selection
  6. Installation of an antenna tuner

Antenna Propagation

  • Depends on antenna type – horizontal or vertical antenna
  • Horizontal antennas have complex radiation patterns, which depend on factors such as height and frequency. E.G, Diople, broadband and long wire antenna
  • Vertical antennas have omni-directional radiation patterns (equal radiation strength in all direction). Hence direction of antenna face is not important, e.g. vertical whip antenna

Distance of Communication

  • Operating Frequency
  • Take-off Angle
  • Transceiver Power

Distance vs Frequency

  • Shorter distances require lower frequencies
    • Larger antenna size
  • Longer distances require higher frequencies
    • Smaller antenna size
  • Size of antenna is inversely proportional to frequency

600-12004-118m x 38m1200-15005-186.5m x 31m2500-100007-285.5m x 26m

Approximate Path Length (km) Frequency Range (MHz) Antenna Mounting Dimension
0-300 2-6 13m x 58m
300-600 3-8 10m x 47m

What is take-off angle?

Elevation plot of the antenna radiation pattern

Take Off Angle Graph

Distance vs Take-Off Angle

Distance vs Take-Off Angle

  • Shorter distances require higher take-off angles
    • Antenna is installed lower
  • Longer distances require low take-off angles
    • Antenna is installed higher
  • Take-Off angle various by how high the antenna is mounted
Take-Off Angle (degrees) Day Time (km) Night Time (km)
0 3000 4500
10 1900 2900
25 1000 1600
40 550 1000
60 250 450
70 150 300
80 80 150

Height of a Fixed Antenna

Height of an antenna can be expressed in terms of physical height, H or wavelength

Height of Fixed Antenna Graph

Height of Fixed Antenna Graph

Controlling Take-Off Angle

For a fixed phjysical height, varying the operating frequency will effect the radiation pattern and hence vary the take-off angle.

For a fixed frequency, varying the physical height of an antenna will also effect the radiation pattern and hence vary the take-off angle.

Controlling Take Off Angle Graph

Controlling Take Off Angle Graph


Leave a Reply