I am very proud to introduce a new antenna design: the Thruster is a portable right-triangular fullwave loop antenna for 20M–6M that features bidirectional gain through the loop along with broadband coverage, low noise pickup, and excellent directional performance. Its unique triangular configuration produces two primary broadside radiation lobes through the center of the loop, providing bidirectional coverage similar to a dipole. Interestingly, due to high current flows along the hypotenuse of the triangle, there is also very good radiation off the side on the loop just 1.2 dBi lower than the bidirectional lobes. Because of that, the radiation pattern is almost three-sided. I want to thank my many KJ6ER beta-testers who helped me improve my free antenna design prior to publication!

The Thruster was extensively computer modeled in 4NEC2 to optimize its efficiency and performance for each band (one-band-at-a-time). The design was developed with an emphasis on achieving useful gain and directional performance while maintaining a pragmatic portable configuration. Because of its fullwave design, it is also resistant to undesired local noise sources. According to the 4NEC2 model, the Thruster delivers an average gain of +1.2 dBi across all six bands, with an average 13 dB front-to-balun-side ratio and 94% structural radiation efficiency across the six-band design.

If you do not have the time, ability or interest to build your own Thruster or any other KJ6ER antenna design, you can purchase a beautifully assembled handmade KJ6ER antenna system as well as many useful accessories on Etsy. More than 380 products have already been sold at the J-Systems Store on Etsy since June 2025 with over 90 perfect 5-star reviews from buyers. We are very proud of our store.