Today I was listening to the AFRTS station on 12133.5 kHz when a numbers station started transmitting on top of it. The stupidity of this astonished me. Everything about numbers stations is mysterious but most of them are probably operated by intelligence services and are used to transmit messages to agents abroad. Many of these transmissions heard in North America are coming from Cuba and are presumably being used to transmit message to agents - i.e., spies - in the U.S. The AFRTS station was just broadcasting general interest programming (news, sports, that sort of thing) but for that very reason it probably has a large audience among military personnel. Starting up the transmission of a numbers station right on top of a United States armed forces broadcasting station, which many U.S. military personnel are listening to, would seem like a pretty stupid thing to do.
Details: Freq: 12133 kHz. Mode: Morse code. Time: 1400-1430 UTC. Good signal. Came on air at 1400. Began with “DWNGA DDAWN URUSN” repeated several times. Then repeated just “URUSN” several times, followed by two BT prosigns. Then into five letter groups. At 1430 sent AR AR SK prosigns and went off air.