Copyright 2013-2016  Collins Collectors Association 51S-1/1A/1F/1AF/1B RECEIVER – An Overview The 51S-1/1A/1F/1AF/1B receiver is designed for USB, LSB, AM, and CW signals in the range of 0.2 to 30.0 MHz. Coverage is continuous in thirty 1 megahertz bands. The … Continue reading 51S-1