Enter your center frequency, number of elements, and physical specs like element diameter, boom diameter, and element shape to calculate your Yagi-Uda antenna's total boom length, along with the reflector, driven element, and first director lengths, plus your antenna's estimated gain.
Total Boom Length
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Reflector Length
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Driven Element Length
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First Director Length
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Estimated Gain
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A Yagi antenna requires at least 3 elements: one reflector, one driven element (dipole), and one director. However, for optimal performance and accuracy of calculations, at least 5 elements are recommended.
Boom diameter affects the antenna's electrical characteristics by influencing the coupling between elements. A larger boom diameter can shift resonant frequencies and require compensation in element dimensions for optimal performance.
A folded dipole has higher input impedance (around 300 ohms) compared to a straight dipole (75 ohms), making it easier to match to transmission lines. Folded dipoles also have broader bandwidth but are more complex to construct.
Insulated elements (mounted on PVC or wood booms) reduce interaction with the boom material, maintaining more predictable performance. Non-insulated metal-to-metal mounting may require slight adjustments to compensate for boom effects.
These calculations provide a good starting point, typically within 2-5% of optimal dimensions. Final tuning may be required based on actual construction methods, materials, and environmental factors.
Yagi antennas work well from HF through microwave frequencies. They're most commonly used in VHF/UHF applications (30 MHz to 3 GHz) where their directional properties and manageable size make them ideal.
The calculator handles unit conversion automatically. For reference: 1 inch = 25.4mm, 1 foot = 304.8mm. Most antenna literature uses metric units for precision in element dimensions.