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TWD Series
Travelling Wave Dipoles 2-30MHz, 3-30MHz & 5-30MHz

These horizontally polarised antennas are suitable for short to medium-distance coverage and provide an economical option to the full Biconical dipole where cost and real estate may be an issue.
The pattern is essentially omnidirectional, however, for long-distance links, the dipole should be orientated broadside to the required direction of communication.
The TWD series is available with two average input power options of 250 watts and 1000 watts.


  • Broadband, ideal for multi-channel or frequency agile synthesized HF radio equipment.
  • 250W and 1000W versions are available.
  • Omnidirectional pattern.
  • Suitable for NVIS coverage, short distance and medium distance coverage.

Technical features

Electrical Specifications

Frequency Range MHz2-303-305-30
Gain dBi2 MHz: -3.9
3 MHz: 1.5
5 MHz: 4.0
10 MHz: 7.1
20 MHz: 6.5
30 MHz: 8.2
3 MHz: -1.8
5 MHz: 2.0
10 MHz: 4.1
20 MHz: 6.0
30 MHz: 8.8
5 MHz: -0.3
10 MHz: 4.3
20 MHz: 8.2
30 MHz: 8.1
Elevation Radiation PatternRefer to plots
Azimuth Radiation PatternEssentially Omni-directional, refer to plots
VSWR<2.5:1 max, 2:1 typical
Maximum Power Rating kW0.25 average, 1 PEP
1 average, 4 PEP
Input ConnectorN-type socket
Impedance (unbalanced), ohmsΩ50

Mechanical Specifications

Recommended Mast Height (not supplied) m12-1810-157-10
Mast spacing m534029
Wind Survival Rating (no ice) km/h (mph)160 (99.4)
Wind Load CommentWind Ratings calculated to AS1170:2.2011

Temperature Specifications

Operating Temperature Range °C (°F)-20 to 70 (-4 to 158)


Material - RadiatorsStainless Steel Wire
Material - InsulatorsPorcelain
Material - SpreadersAluminium


Shipping informationPacked weight [kg (lb)]Packed volume [cubic m (cubic ft)]
TWD23025 (55)7.5 (265)
TWD33022 (48.5)7.5 (265)
TWD53020 (44)7.5 (265)

External Document Links