HF V-Dipole Antenna

High-Frequency (HF) dipole antennas are essential tools for long-range communications, especially within the 3–30MHz HF Band.
In this article, I’ll take you through how I assembled a practical and low cost HF dipole antenna:

   1. cover its working principles
   2. parts needed
   3. length calculations
   4. impedance matching
What is a dipole antenna?
An HF dipole antenna is a two-conductor antenna optimised for high-frequency radio transmission and reception. It typically operates on bands such as 3.5 MHz, 7 MHz, 14 MHz, and above.
Key Features
  • Supports long-distance communication (over hundreds or thousands of kilometers)
  • Simple structure: two arms fed at the center
  • Horizontal or inverted-V installation
  • Works well with minimal ground reflection
Parts needed
Antenna mounting plate:
Available from AliExpress for about £23 Find them here: AliEXpress Includes two telescopic antenna elements, each 5.5M long
Available from AliExpress for about £23

Find them here: AliEXpress

Includes two telescopic antenna elements, each 5.5M long

Tripod Mount:
An essential tripod mounting pole: Available from AliExpress, about £3

Balun (Balanced-to-Unbalanced Transformer:
A 1:1 Balun available from AliExpress or Amazon about £20
Find item here: AliExpress
Helps to improve matching and reduce antenna noise

Calculating arm lengths (adjust as necessary):

To determine the length of each dipole arm: Length (in meters) = 143 / Frequency (MHz)

Example element lengths (same each side):
For 7 MHz operation  (40-metre band): Total length ≈ 143 / 7  ≈ 20.43 meters → element ≈ 10.2 meters. Adjust both sides for fine-tuning.

For 14 MHz operation (20-metre band): Total length ≈ 143 / 14 ≈ 10.21 meters → Each element ≈ 5.1  meters. Adjust both sides for fine-tuning.

For 18 MHz operation (17-metre band): Total length ≈ 143 / 18 ≈ 7.9   meters → Each element ≈ 3.95 meters. Adjust both sides for fine-tuning.

For 21 MHz operation (15-metre band): Total length ≈ 143 / 21 ≈ 6.8   meters → Each element ≈ 3.4  meters. Adjust both sides for fine-tuning.

For 24 MHz operation (12-metre band): Total length ≈ 143 / 24 ≈ 5.74  meters → Each element ≈ 2.87 meters. Adjust both sides for fine-tuning.

For 29 MHz operation (10-metre band): Total length ≈ 143 / 29 ≈ 4.93  meters → Each element ≈ 2.46 meters. Adjust both sides for fine-tuning.

For 54 MHz operation  (6-metre band): Total length ≈ 143 / 54 ≈ 2.64  meters → Each element ≈ 1.32 meters. Adjust both sides for fine-tuning.