|Voice||Female, automated, variable speed|
|Known counterpart stations||E13|
E13 and G13 were short-lived number stations that operated at the end of the Cold War. They were used by American and West German intelligence agencies CIA and BND during destabilization operations in East Germany.
|735||735||735||68697||25||Five 1 kHz beeps||563-36 843-76 400-65 451-65 ...||Ich wiederhole||563-36 843-76 400-65 451-65 ...||Ende|
|3-figure traffic validity indicator||One-time pad positioning group||Amount of 5-figure groups in the message||5-figure single groups, with a pause after the third digit.||"I repeat"||5-figure single groups, with a pause after the third digit.|
|Repeated for 5 minutes|
The transmissions always started at the top of the hour. Note extensive similarity of the format to the CIA number station G05.
If the middle digit in the 3-figure ID was even, the transmission contained an actual message, otherwise the groups were meaningless.
G13 schedule from around 1991:
|Mon||Tue||Wed||Thu||Fri||Sat||Sun||UTC||Frequency 1||Frequency 2|
|x||20:00||7650 kHz||11849 kHz|
|x||22:00||4395 kHz||16235 kHz|
|x||20:00||4395 kHz||16708 kHz|
|x||21:00||4395 kHz||15325 kHz|
|x||11:00||7650 kHz||18970 kHz|
|x||19:00||5351 kHz||7830 kHz|
|x||x||11:00||8970 kHz||10255 kHz|
|x||19:00||8490 kHz||10255 kHz|
|x||11:00||9870 kHz||10255 kHz|
|x||18:00||5351 kHz||7830 kHz|
Based on descriptions from Simon Mason's 1991 book "Secret Signals" and Langley Pierce's 1994 book "Intercepting Numbers Stations"