Antenna Calculator天线尺寸计算器
输入频率，快速算出偶极天线、倒 V 天线、1/4 波长垂直天线、5/8 波长垂直天线和三单元八木天线的关键尺寸，支持米与英尺切换。计算基于 468/f、492/f 等经典公式，适合架设前快速下料、野外通联前规划天线。实际制作请预留余量，并用天线分析仪做最终微调。
Enter a frequency to get key dimensions for dipole, inverted-V, quarter-wave vertical, 5/8-wave vertical and 3-element Yagi antennas, in meters or feet. Based on classic formulas such as 468/f and 492/f, ideal for cutting elements before a build or planning antennas for portable operation. Leave trimming margin and fine-tune with an antenna analyzer.
Enter a frequency to get wire lengths for common antennas, instantly.输入频率，立即得到常用天线的导线长度。
Frequency (MHz)频率（MHz）
Primary unit首选单位
—Wavelength 波长 λ
Results计算结果
| Antenna天线 | Meters (m)米 | Feet / Inches英尺 / 英寸 |
|---|
Practical tip / 实用提示： Formulas assume bare wire in free space. Real wire has a velocity factor (~0.95–0.98), so cut 3–5% long and trim while checking SWR. Height above ground and nearby objects also shift resonance — always verify with an SWR meter or analyzer.
公式按自由空间裸线计算。实际导线存在速度因子（约 0.95–0.98），建议先留长 3–5%，再边测驻波边修剪。离地高度和周围物体会影响谐振，请务必用驻波表或天线分析仪实测确认。