 Arco greatly increased the power and range of early transmitters.In this regard he surpassed the "Löschfunkensender" of Max Wien, which had already exhibited a substantially better efficiency than the "Knallfunkensender" of Ferdinand Braun, and in addition could send on a narrow frequency band.Arco's greatest service lay in the development of the large radio station at Nauen, 20 miles west of Berlin, thereby helping Telefunken to become a firm of worldwide reputation.