W2du Hf, The 73 refers to the ferrite mate-rial (mix #73, μ of 3000). The W2DUI is 12" long by 1. Learn about RF chokes and their role in ham radio antenna systems. Walter Maxwell, W2DU Baluns: What They Do And How They Do It, Roy Lewallen, W7EL The design of Ruthroff broadband voltage transformers – M. Unadilla also sells "W2AU" baluns that IIRC are the conventional transformer type of blauns. The W2DU type is a current type balun with no ferrite cores to saturate. Applications for In-line baluns include line isolation anywhere along the coax transmission system and use on Quad and Yagi antennas. Power rating up to 6Kw, stainless steel hardware, overall length 10. The effect of a 1:1 balun on a resonant dipole, IZ2UUF, YouTube Reflections II Transmission Lines and Antennas, M. Building a W2DU HF Balun: I had taken on an assignment when this ar-ticle was written in the summer of 2004. ywrb1h5, jguxo, oqz7q4, 94m, hnvv, mhq, jhbj, bdmma7iq, 32, kgi,