Founded in a small hotel room rented in 1972, MFJ Enterprises has become a world leader in amateur radio components. As the hobby of hobby radio has evolved, MFJ has continued to develop new products to meet the needs of amateur radios. From the original high selectivity filter that started it all to the latest DX technology,MFJ Enterprises now offers antenna tuners, vertical antennas, wattmeters/SWR, SWR analyzers, Audio filters, power supplies and DC strips, dummy loads and more.