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- Energy gain - low frequency: 27.0 ± 1 dBi
- Energy gain - high frequency: 28.0 ± 1 dBi
- Beam width: 6.8°
- Dimensions: Ø 68 cm
- Dual polarization: Vertical and horizontal (precise adjustment ±5°)
- Energy gain - low frequency: 29.5 ± 1 dBi
- Energy gain - high frequency: 30.5 ± 1 dBi
- 3 dB beamwidth: 5.0°
- Dimensions: Ø 90 cm
- Polarization: Dual – vertical and horizontal
- Energy gain - low frequency: 29.4 ± 1 dBi
- Energy gain - high frequency: 30.0 ± 1 dBi
- Beam width: 5.0°
- Dimensions: Ø 90 cm
- Polarization: Dual – vertical and horizontal (precise setting ±5°)
- Energy gain - low frequency: 31.5 ± 1 dBi
- Energy gain - high frequency: 32.6 ± 1 dBi
- Beam width: 4.2°
- Dimensions: Ø 120 cm
- Energy gain - low frequency: 34.8 ± 1 dBi
- Energy gain - high frequency: 36.0 ± 1 dBi
- Beam width: 2.8°
- Dimensions: Ø 180 cm
- Connector type: N-female
- Energy gain: 30.0 ± 0.5 dBi
- Beam width: 5.2°
- Connector type: N-female
- Dimensions: Ø 90 cm
- Polarization: Vertical and horizontal
4.7 MHz antennas are devices designed for operation in the 4.7 MHz frequency band, which is frequently used in amateur and professional shortwave (HF) communications, especially in applications requiring stable and long-range coverage. This band, located in the medium wave range, is characterized by good propagation properties, allowing for long-distance connections, both day and night, although with varying efficiency depending on the time of day and ionospheric conditions.
Advantages of 4.7 MHz Antennas:
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Long Range: Thanks to the favorable propagation properties of the 4.7 MHz band, these antennas enable long-distance communications, which is crucial for DX (long-range) communications.
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Connection Stability: Under the right conditions, the 4.7 MHz band offers relatively stable connections that are less susceptible to signal dropouts than higher frequencies, especially at night.
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Versatile Applications: These antennas are used in amateur radio (e.g., the 60-meter band), maritime, and aviation applications, as well as in military and emergency services systems, where reliable communication over medium distances is a priority.
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Interference Immunity: Compared to higher frequencies, the 4.7 MHz band may be less susceptible to certain types of local interference, improving received signal quality.
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Variability of Design: Various types of 4.7 MHz antennas are available, such as dipoles, verticals, magnetic loops, and shortened antennas, allowing for customization to specific installation conditions and user requirements.
What to Consider When Choosing a 4.7 MHz Antenna?
Choosing the right 4.7 MHz antenna should be guided by several key factors that will ensure optimal performance and user satisfaction:
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Available Installation Space: This is perhaps the most important factor. 4.7 MHz antennas are often physically long. If space is limited, consider short antennas, magnetic loops, or vertical antennas, which require less horizontal space.
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Antenna Type:
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Power Handling: Ensure that the antenna you choose can safely handle the power you intend to transmit at. Maximum power is always provided by the manufacturer.
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Material and Build Quality: An antenna is a long-term investment. Choose antennas made of durable, weather-resistant materials such as aluminum, stainless steel, or high-quality plastics.
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Resonance and SWR (Standing Wave Ratio): Ideally, the antenna should be resonant at 4.7 MHz, meaning the SWR should be close to 1:1. Pay attention to the antenna's operating bandwidth (the bandwidth over which the SWR is acceptable).
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Ease of Installation and Maintenance: Some antennas are easier to install and require less maintenance than others. If you are inexperienced, look for models with clear instructions and a simple design.
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Budget: Antenna prices can vary significantly. Set your budget, but remember that investing in a better antenna often translates to better call quality and greater satisfaction.
