The Light Beam Multi-band Antenna has been developed for Hams who want one antenna which enables them to operate on multiple amateur bands. Based on the tried and true Moxon antenna design, the LBM – 17M+20M antenna provides excellent performance on both the 17 Meter and 20 Meter bands. Smaller than comparable antennas, the LBM is 70% the width of a full sized multiband beam or dipole and has a short turning radius, yet handles a maximum allowable power input of over 1.5 KW and is over 90% efficient. There are NO lossy traps included in this design – almost all of the power you put into the antenna is radiated. The antenna has four elements, two of which are active on each band. Element spacing has been optimized for maximum gain and Front to Back ratio. The antenna impedance is 50 Ohms. No matching network, device, or antenna tuner are needed while only a 1:1 Balun is needed to translate the interface from the balanced antenna to your unbalanced coaxial cable.
In addition, the LBM series of antenna design has been optimized to provide excellent performance at only 30 feet above the ground. The antennas are light-weight and have low surface area thereby reducing wind loading of the antenna and antenna support structure. Consequently a heavy-duty tower and rotor are not needed. The elements are also reinforced to withstand ice and snow loading. The boom is a very strong laminated design.
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