XPA
| Enigma ID | XPA |
| Name | |
| Frequencies | |
| Status | Active |
| Voice | N/A |
| Emission mode | USB; 17-tone MFSK, 10 Bd, 40 Hz |
| Location |
Moscow, Russia
|
| Activity pages |
XPA is a digital mode of the Russian 7 operator. It utilizes a custom 17-tone MFSK system.
Null format:
| 761 761 761 | 000 | 03683 | 00001 | 00000 | 35663 |
| 3-digit ID (thrice) |
5-digit group with "0" in front |
5-digit group with "3" or "4" in front |
Traffic format:
| 761 761 761 | 1 | 08733 | 00113 | 30757 78052 ... 32479 32764 |
| 3-digit ID (thrice) |
Message count |
5-digit group with "0" in front |
Group count minus 3 padded to 5 digits |
5-digit single groups |
The 3-digit ID and the message count appear only at the beginning of the broadcast. Multiple messages within a single transmission are separated using "00000 00000."
All XPA schedules are twice weekly and consist of 3 identical transmissions 20 minutes apart. Each successive transmission is 1-2 MHz lower or higher in frequency. The frequencies are typically changed on a monthly basis.