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The means of receiving orders from his superiors, via shortwave transmission of a code consisting of numbers, has been in use for decades by spy agencies from a
by JoeDaDude 10y ago
The means of receiving orders from his superiors, via shortwave transmission of a code consisting of numbers, has been in use for decades by spy agencies from around the world. Radio enthusiasts have been listening to these stations since the end of World War II.
http://www.spynumbers.com/ http://www.spynumbers.com/
http://priyom.org/number-stations http://priyom.org/number-stations
http://www.numbers-stations.com/ http://www.numbers-stations.com/
http://www.bbc.com/news/magazine-24910397 http://www.bbc.com/news/magazine-24910397
- quirkafleeg 10y agohttp://irdial.hyperreal.org/the%20conet%20project/ http://irdial.hyperreal.org/the%20conet%20project/
- danielvf 10y agoEven more interesting is that old radio receivers would give off faint sidebands when listening. This, you could drive around with the right gear and find radios listening to a numbers station. https://en.m.wikipedia.org/wiki/Superheterodyne_receiver https://en.m.wikipedia.org/wiki/Superheterodyne_receiver
- keithpeter 10y agoDo you mean that you could tune into the local oscillator in the spy's receiver that would be displaced from the transmitted frequency by the value of the intermediate frequency? E.g. number station on 6000Khz and IF 465KHz so local oscillator 6465KHz? What happened when receivers went over to up-conversion and frequency synthesis?