433 MHz Dipole Antenna (SWR 1.4)

This is a high-efficiency dipole antenna design specifically optimized for the 433 MHz band. It is perfect for LoRa, Meshtastic nodes, or general Amateur Radio (UHF) use.

By using 10mm aluminum tubes , this antenna provides a wider bandwidth and better durability compared to thin wire antennas. During my tests with a NanoVNA, I achieved a solid 1.4 SWR at 433.900 MHz.

Technical Specifications

- Element Material: 10mm Aluminum Tube - Wing Length (Each Side): Exactly 136 mm (Note: This is shorter than theoretical calculations due to the 10mm tube diameter and velocity factor, providing the best resonance). - Center Gap: 10 mm - Target Frequency: 433 MHz - Measured SWR: 1.4 Build Notes

The 3D printed parts are designed to hold the elements securely in place. Ensure the gap between the two aluminum tubes is exactly 10mm to maintain the tuned impedance.

For a step-by-step build guide and more detailed RF analysis, check out my blog post:

UHF Dipole Antenna Build Guide (Turkish)