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A ghostly radio station that no one claims to run

bbc.com

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Re: A ghostly radio station that no one claims to run

#41

Post by calebm »

sillysaurus3 wrote: post #39
jankotek wrote: post #36

> the Buzzer operates at a relatively low frequency known as “shortwave”. This means that – compared to local radio, mobile phone and television signals – fewer waves pass through a single point every second. It also means they can travel a lot further. Nice explanation.

Is it? If you imagine a fixed point in space, a short wave would mean more waves pass through it every second, not less. Short waves have more energy (they have bounce up and down more quickly) which allows them to travel further.

It's true that "shorter" waves would mean higher frequency, but "shortware" radio uses longer (lower-frequency) waves, relative to most other modern radio systems, so it is true that "fewer waves pass through a single point every second".

Also, it is true that for a given amplitude, a higher frequency wave does contain more energy, but typically, higher frequency waves don't travel as far. Shortwave radio travels particularly far because they happen to be in the right frequency to bounce off the ionosphere, which allows them to travel further than line of sight.

Re: A ghostly radio station that no one claims to run

#42

Post by burkaman »

sillysaurus3 wrote: post #39
jankotek wrote: post #36

> the Buzzer operates at a relatively low frequency known as “shortwave”. This means that – compared to local radio, mobile phone and television signals – fewer waves pass through a single point every second. It also means they can travel a lot further. Nice explanation.

Is it? If you imagine a fixed point in space, a short wave would mean more waves pass through it every second, not less. Short waves have more energy (they have bounce up and down more quickly) which allows them to travel further.

Right, but "shortwave" waves are longer than TV and cell phone waves.

Re: A ghostly radio station that no one claims to run

#43

Post by lb1lf »

vvanders wrote: post #37
TheRealEdAbbey wrote: post #32

Earlier quoted context omitted.

Yep, PSK31 has a baud rate of 31.25 - that's literally 31 bits per second. There's no practical use for that in modern commercial or consumer applications. In amateur bands, symbol rate below 28 MHz is limited to 300 baud.

And anything in the 2M band is also symbol rate limited(I want to say it was 1200baud but I could be wrong). It's really frustrating if you want to do any development with digital modes. [edit] Looked it up, it's a 19.6k symbol rate limit(rather than leave it open and restrict bandwidth). You can carry a ton of data on 2M if you wanted but legally you can't exceed the speed of an old dial up modem.

Are US ham bands really symbol rate (rather than bandwidth)limited?

Here in LA (Norway, for the ham prefix challenged), we can modulate in whatever way we feel like on 2M, as long as the signal bandwidth does not exceed 18kHz.

(So, using a clever modulation scheme, you could get very close to the Shannon limit for the given channel bandwidth and noise level - assuming a very healthy 30dB S/N, one should be able to wring approx. 180kbps from an 18kHz channel. (Granted, in the real world with filters without infinitely steep skirts we'd get nowhere near this - but, let's say you could get 1/3 or so without trying too hard.)

Re: A ghostly radio station that no one claims to run

#44

Post by Xylakant »

sillysaurus3 wrote: post #39
jankotek wrote: post #36

> the Buzzer operates at a relatively low frequency known as “shortwave”. This means that – compared to local radio, mobile phone and television signals – fewer waves pass through a single point every second. It also means they can travel a lot further. Nice explanation.

Is it? If you imagine a fixed point in space, a short wave would mean more waves pass through it every second, not less. Short waves have more energy (they have bounce up and down more quickly) which allows them to travel further.

It's shortwave (1.6MHz - 30MHz) and not "shorter wave". Radio and TV commonly use FM or UHF (300MHz upwards). So the explanation is technically correct: more waves pass a given point in space.

Re: A ghostly radio station that no one claims to run

#45

Post by wbl »

jpalomaki wrote: post #33
westbywest wrote: post #21

Earlier quoted context omitted.

As mentioned in the below comment, the author buried the probable lede: most of the time transmission is a placeholder to discourage others from using the band. During exceptional circumstances (as defined by the station's operator), it will transmit coded messages to global/regional operatives. E.g., to coordinate espionage when conventional communications are offline.

That constant sound is also useful for the spies. Without that it would be hard to know you have tuned on the right frequency (I'd assume they would use some pretty simple and low tech radios).

They would use commercially avaliable radios in the place they live to deter suspicion.

Re: A ghostly radio station that no one claims to run

#46

Post by criddell »

besselheim wrote: post #35
wichert wrote: post #5

For the lazy who were hoping to find an audio clip in the article: you can find some here: http://www.sigidwiki.com/wiki/The_Buzzer_(ZhUOZ_MDZhB_UZB76)

The WebSDR at http://websdr.ewi.utwente.nl:8901 (based in the Netherlands) can be used to hear the station as it is broadcast. Set to 4625 kHz, USB.

Neato - it's picking up the buzzer station right now!

Re: A ghostly radio station that no one claims to run

#47

Post by sillysaurus3 »

calebm wrote: post #41
sillysaurus3 wrote: post #39

Earlier quoted context omitted.

Is it? If you imagine a fixed point in space, a short wave would mean more waves pass through it every second, not less. Short waves have more energy (they have bounce up and down more quickly) which allows them to travel further.

It's true that "shorter" waves would mean higher frequency, but "shortware" radio uses longer (lower-frequency) waves, relative to most other modern radio systems, so it is true that "fewer waves pass through a single point every second". Also, it is true that for a given amplitude, a higher frequency wave does contain more energy, but typically, higher frequency waves don't travel as far. Shortwave radio travels par…

Thanks!

Re: A ghostly radio station that no one claims to run

#49

Post by jimmytucson »

rosbrith wrote: post #11
wichert wrote: post #5

For the lazy who were hoping to find an audio clip in the article: you can find some here: http://www.sigidwiki.com/wiki/The_Buzzer_(ZhUOZ_MDZhB_UZB76)

A few years back some brave souls visited the site of the old transmitter at Povarovo and posted some pictures and video of the trip: http://bydunai.livejournal.com/749.html

They link to a Wired article about the station from 2011: https://www.wired.com/2011/09/ff_uvb76/all/1

Re: A ghostly radio station that no one claims to run

#50

Post by jacquesm »

criddell wrote: post #4

I read this article last weekend and after reading it, I put batteries in my shortwave radio to see what was out there. Turns out, there's pretty much nothing. I couldn't hear anything on 4625 kHz. I let my receiver scan and when it was done I checked out what it detected and found absolutely nothing interesting. The most powerful signals were Christian broadcasts that had a kind of doomsday feeling about them. It se…

It might be single sideband, try USB or LSB.
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