4:1 Balun Dipole Center

The Balun (Balanced / Unbalanced) Transformer is a critical piece of antenna design on HF frequencies. Unlike the higher bands, the antennas on HF are exceptionally large, leading to compromise in length and physical footprint. This leads to variables in matching impedance at the feedpoint and back to the radio.  In layman's terms, this means you might want to have a transformer at the center if you're building a wire antenna on HF (and yeah, you should be!). The 4:1 takes a load of up to 200 Ohms and transforms it down to 50, making the tuner on your HF radio have to perform less work to create a match. Overall its more efficient and is why Hams usually have lots of Baluns hanging around the bench for that next antenna design. In addition it cuts down on static and common mode interference by creating a choke at the feedpoint, making shortwave reception much better on the same antennas.  The 4:1 is my personal choice due to its versatility and I've used this design on several antenna