Amateurs had been operating radiotelephone on the 80-meter band between 3,500 and 3,600 kHz since it had first been permitted in late 1925.1 To do so they had to return their licenses to their local radio supervisor for endorsement. On the 150-meter band, phone already dominated operation. And as the broadcasting boom continued, phone’s popularity grew as a specialized pursuit for some amateurs on both bands. For others it was a source of QRM since every phone allocation shared space … Continue reading →