Hello Gerhard, Like Jim already said, this most likely is NDB BRK-408, Wien / Schwechat / Bruck, located in JN88ib. It uses AM with a keyed tone of nominal 1020 Hz. It often has a strong signal in th
Dear group! I'm working on a new DC-CW receiver and while testing, I found a CW-Signal on 137.00 sending "BRK" every 10 seconds. I don't believe that this is a real signal on this QRG rather some mix