BULGARIAN BETTY

The nickname of this station, which went off the air in December, 1990, was given to it by various American numbers station monitors. In fact, because of its all night broadcasting schedule, it became a regular logging for listeners in the United States. The language used was variously described as Russian, Polish, Bulgarian, Serbo-Croat and - on a Radio Netherlands report, even Macedonian. The interval signal used was a five note rising scale tune which was followed by the group headings. The messages were sent in the five figure format. It was a very monotonous and boring transmission, even as numbers stations go. At the end of its life it was using two frequencies: 4030 and 4882.5, not in parallel. However, these transmissions were sent at various times between 1600 and 0600. Other frequencies noted during Betty's career were 2805 (unusually low), 3225, 4006, 5157, 5247, 5445, 5860 and 7740.  Here is some additional information from Langley Pierce's book.

Czech Intelligence the Statni Bezpecnost , acted for many years as the British arm of the KGB; simply put, Czech citizens could enter the UK much easier than a Soviet! From this arrangement came many of the Cold War's most unusual spies. The progressive modernisation that swept the Eastern Bloc in the late 1980's first took hold in Czechoslovakia in 1989, yet it was not until Tuesday, 1st January 1991 that the first of two Spy number stations was to send its last messages. The station that remains is believed to be the same station the Czech Spy Erwin Van Haarlem received his instructions from!

Format 1

1. Transmission Format Transmissions began at half hourly intervals, with repeat broadcasts commencing fifteen minutes late. The preamble consisted of a series of five tones, repeated 38 times, followed by the traffic list, repeated 4 times.

Preamble: Series of five tones.
333 333
12022 12022 70 70
67835 67835 16 16
4820048200 1818
30528 30528 26 26
Message: Pozor Pozor
12022 12022 79 79 70 70
67738 67738 48538 48538 25540 25540.... 79 79 70 70

Each individual message is presented in this format, with the transmission ending with: Conet Conet.

2. Circuit Numbers. The traffic list begins with a three digit circuit number, either 333 or 111, indicating the frequency' on which the repeat broadcast will be carried. The primary' frequency' is that which becomes active with the first broadcast, and is dependant on what schedule is in operation.
Primary 111 222 333 444 555
           4030.0 3225.5 - 4882.5 - -
           4030.0 3225.5 - 5447.0 -
           4882.5 4030.0 - 5860.0 -

The circuit number 555 was used by a rare idler form of this transmission, the format being the ubiquitous "555 555 555 000," terminating after five minutes with "Conet Conet."
Each message is introduced by three numbers.
12022 79 7
The traffic address indicator is made up of two individual components.
97152 Key group
25970 Agent number
12022 Indicator
The key group is taken from the agent's one-time pad, and to that number is then added the agents own personal agent number. In this case 25970, giving the indicator 12022. The agent, knowing of this number in advance of the transmission, need only listen to the traffic list. If his message number does not appear, then he knows that there is no traffic for him. Since each address number is enciphered, traffic to individual addressees over any length of time cannot be distinguished from other traffic, hence any attempted traffic analysis will reveal nothing about the agent. All traffic emanating from this station is to be considered valid.

The group coordinate index is one of the most perplexing additions to any numbers traffic. This group is encoded, and once decoded, reveals in row and column coordinates the starting position on the one time pad. Subsequent traffic is presented in non-standard Czech by a computer synthesised female voice.
1. yedena  6. shest
2. dva        7. feedoom
3. see        8. vossoom
4. shtiri      9. deviet
5. pyet       0. noll
 Hothor - Ready     Conet - End

Czech 'illegals" and agents alike are contacted by their spymasters in Prague via the Liblice transmitter site, some 30 miles east of the capital. This site was also host to the OLB5 and OMA time signal stations, OLB5 having been previously housed at Podebrad. However, due to its close proximity to the transmitter, the OLB5 signal could often be heard bleeding over onto the numbers transmissions. Both OMA on 2500 kHz and OLB5 on 3170 kHz were dropped on 3 May 1990. Officially, the station claimed that the transmissions were dropped due to financial cuts in the Academy of Sciences budget.

Czech deep cover agents and sleepers are still however receiving their instructions through a second network.