Numbers stations transmit information to agents in the field. Basically, it is a transmitter transmitting one way ( to the agents ) information and orders. The last one that made public notoriety was In 2006 Carlos Alvarez and his wife Elsa Alvarez were charged with espionage and acting as illegal agents for Cuba.
The 2009 case against Kendall Myers also included years of receiving direction via short wave spy numbers stations. Since he was working for the Cubans it is a pretty safe assumption this was V02/M08/SK01.
I have heard that there might have been some SW reception and possible numbers station stuff in the 2010 Russian spy ring case (the “Anna Chapman” case, although few remember the other 9 people involved).
Numbers stations may, or may not be passing out information. Just because a numbers station is transmitting ( In code ) does not necessarily mean it is information at all. The transmitter could be transmitting "Bogus" information for others to try to intepret and decode, or it could be passing out accurate and reliable information. Between the National Security Agency, the Central Intelligence Agency, and a host of other intelligence agencys that employ mathmeticians to make reason of numerical codes...I would say that the "Numbers" thing is well on top of.
Some numbers stations never send a “null” message. This means you can not know which transmissions contain good data and which are “padding” just sent so that operational tempo can not be derived from message traffic. Other stations send regular and clearly defined “null” messages when they have no traffic for their specific assets.
A properly used OTP is going to be completely secure. All the math in the world thrown at it will not crack it. Or rather, it will crack it and an almost unlimited number of possible solutions, and you will never know which “decoded” message is the correct one.
However, it is important to record and store all such transmissions, even if you can not read them today. A future case might include seizure of the ability to decode past transmissions.
"Enemy" agents all over the world, receiving orders from their home base / country, so they will not get caught. Enemy agents receiving messages only, instead of performing two-way communications and taking a chance of getting arrested and incarcerated, opening them up to questioning and interrogation. Agents receiving only, not getting caught in a two way broadcast through signal triangulation..and other means of decyphering radio communicattion locations.
Assets using a OWVL (One Way Voice Link, this is what a Numbers Station is) are not undetectable. Certainly it is much safer than using a transmitter. But, the asset must have the ability to decode the transmission, and this means he/she must make contact at some time, and probably periodically, to receive the latest decryption information. If this is distributed electronically it becomes very trackable. Probably the most safe would be using dead drops and multiple cut-outs. But once one link in the chain is compromised this endangers every other link.
Also, the act of reception of the signals itself can be tracked or confirmed to incriminate the asset.
A traditional superheterodyne receiver uses an LO, Local Oscillator. And LO leakage can be tracked to determine what frequency a person is monitoring at any given time. It can also be used to locate/track whoever is using it within a limited range. This range might be much larger than many people think, during World War II German U-boats used LO leakage to track and target Allied merchant shipping. Today it is used in certain auto parking structures to sample what radio station each car entering is tuned to, so that advertising budgets can be most efficiently used to reach the intended market.
Also, research “Operation Rafter”, a British effort.
Numbers stations transmit usually in AM band at high wattage. Simple computer research can give you pics of transmitter sites, antennas, FBI investigations, and a slew of other valuable intelligence.
AM is a modulation technique, not specifically a band. In the US we have what is called the “AM broadcast band”, but this frequency range is seldom used by numbers stations.
The use of AM (DSB with full carrier) by numbers stations is older information. Today many, maybe even most, numbers stations do not use AM modulation. Many of the old school established numbers stations still use AM, but most “new” numbers stations use SSB, with USB being the most popular. The use of USB with carrier is also seen, and could be called an AM mode, and has replaced full AM in some older stations.
Many numbers stations use Morse code. Again, many of the older ones use “MCW”, or Modulated CW, and this is an AM technique. But, many also use true CW and pretty much all of the newer ones use CW.
Some numbers stations are known to have converted or started to use to digital modes, others are suspected of having done so. Example, Cuban V02/M08 is associated with digital mode SK01. And the Chinese language numbers station V26, and its CW sister station M97, are often seen following a digital mode referred to as the “Chinese 4+4 modem”. XPA and XPA2 are assumed to be digital modes for Russian intel, and are sometimes seen on frequencies known to be used by Russian based numbers stations.
As for high power, in the past many numbers stations used broadcast facilities. While still a fact with some stations this habit is in decline, particularly with Oriental stations. With that said, it does apear the recently re-activated V16 might be using BC facilities.
You can get numbers station recordings, numbers station frequencys and times...with internet research
Numbers station schedules, the frequencies and times they use, change often. If you do find information on the net look at the age of the information. The older it is the less likely it is to still be usable.
For example, in February of this year South Korean numbers station V24 had a major change and stopped using several frequencies. They did not add new frequencies but rather condense their operations form 8 to 4 frequencies. This means the schedule on the remaining 4 frequencies changed. At the same time they also changed the voice used in their numbers.
Another example, Chinese numbers station V16 recently appears to have been re-activated, it had not been reported since before 2000. So any past schedules you find for it, pre-2000, would not apply.
And some stations just have seasonal changes, they may have one schedule for winter, and another for summer.
Some good sources of numbers station data/schedules:
The Enigma 2000 web site:
ENIGMA2000
The Numbers and Oddities web site:
Numbers stations home page
The Spynumbers web site :
Spy Numbers Stations Shortwave Radio
The Priyom.org web site:
Priyom.org - Priyom.org
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