SCR-274N equipment: | 1 - BC455-B 6-9.1 mc, no mods OOPS!!! This BC-455-B in fact has been modded. Sorry about that. There is a replacement panel in the front below the main tuning dial with a toggle switch and a knob. Most likely a BFO mod....or maybe part of a sub-space transporter. Who knows?? 73 Rich W3OSS