XPA2 Polytones – Russian Digital Numbers Station

XPA2 was first heard in May 2006 and is very similar to XPA. Although it uses a 7.5 baud rate and has higher pitched tones. Used to operate at 3 different speeds. Used to send in both AM and USB mode with no change in the baud rate.  XPA2 will also usually send out test tones ahead of time like XPA does.

Tone Functions

1000 Hz – Space 1030 Hz – Low Sync Tone
1045 Hz – Transmission End 1060 Hz – Repeat Previous
1100 Hz – 0 1115 Hz – 1
1130 Hz – 2 1145 Hz – 3
1160 Hz – 4 1175 Hz – 5
1190 Hz – 6 1205 Hz – 7
1220 Hz – 8 1235 – 9

Station Structure

Begins with 2 minutes of high and low lead in tones, then sync tones, decode key, group count, 3rd and 4th groups unknown use.
Additional messages are separated by 00000 00000

xpa2null

 

Numbers Station Summary

Nickname: Polytones
Activity: Active
Emission Mode: USB
Believed Country of Origin: Russia
Related Stations: E07, G07, S07, V07, M12, XP, XPA, XPB