M13
| Enigma ID | M13 |
| Name | |
| Frequencies | |
| Status | Inactive |
| Voice | N/A |
| Emission mode | ICW |
| Location |
Bulgaria
|
| Activity pages |
M13 belonged to one of Bulgarian intelligence agencies. Morse code counterpart to E18, G22, S04. Last heard in early 2006.[1]
The transmission format is given below. The speed was 12 words per minute, and one dash was used for zero.
| Preamble | Message | Repeat | Outro | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 458 | BT | 195 | 20 | BT | 95404 17097 16052 ... | BT | 458 | BT | 195 | 20 | BT | 95404 17097 16052 ... | BT | Three long dashes |
| 3-digit ID | Serial number | Group count | 5-figure single groups | 3-digit ID | Serial number | Group count | 5-digit single groups | "0 0 0" | ||||||
| Repeated for 5 minutes | Repeated for 1 minute | |||||||||||||
M13 was significantly more active than its voice counterparts. M13 transmitted every day, and constantly changed times and frequencies. All the transmissions took place in the 00:00-10:00 and 16:00-23:59 time frames. The average message length was 23 groups. The messages were repeated in one of the following patterns:[2]
- On the same day, 1 hour later, on the same frequency
- On the same day, 1 hour later, on a different frequency
- On the next day, at the same time, on the same frequeny
- On the next day, at the same time, on a different frequency
References
- ENIGMA Control List, Revision #25
- Numbers & Oddities #4 (July 1998) [accessed September 18th, 2014]