Passage: Extreme interference at the longer edge of the 150<unk>200 meter band <unk> the official wavelengths allocated to amateurs by the Second National Radio Conference in 1923 <unk> forced amateurs to shift to shorter and shorter wavelengths; however, amateurs were limited by regulation to wavelengths longer than 150 meters (2 MHz). A few fortunate amateurs who obtained special permission for experimental communications at wavelengths shorter than 150 meters completed hundreds of long distance two-way contacts on 100 meters (3 MHz) in 1923 including the first transatlantic two-way contacts.By 1924 many additional specially licensed amateurs were routinely making transoceanic contacts at distances of 6,000 miles (9,600 km) and more. On 21 September 1924 several amateurs in California completed two-way contacts with an amateur in October. On 19 October 1923, amateurs were limited by regulation to wavelengths longer than 150 meters (2 MHz).
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