Gregory's Server(the frequency was quite a bit below standard AM broadcast, typically around 15-20KHz.)
|
11 comments
 and if you can't make it out to Sweden, there are virtual tours available: https://alexander.n.se/en/virtual-visit-to-saq-grimeton/ for further reading, here's a useful paper. https://www.navy-radio.com/xmtrs/vlf/alexanderson-mayes-1975.pdf  @tubetime OMG it runs off 2-phase because it's from a very particular time and place in the US. @tubetime OMG the air-quenched relays are scary, and they're just right out there. @tubetime Thanks for posting this; on my list for my next visit to Scandinavia. @tubetime apparently someone made a modern receiver out of relatively equivalent-level technology http://www.wireless.org.uk/mechrx.htm  @tubetime |
incredibly, there is still an *operational* Alexanderson transmitter! it is called SAQ Grimeton and they fire it up twice a year.