[Spooks] Unid 14 and 18 Mhz Solved

[Tom Norris]

Indeed, it appears this is what it is.

Bubble jammer heard on 6030, harmonic on 12060 (though underneath
the station currently on the air there ) I'll bet that earlier when
the 14 Mhz signal was heard, I would have been able to clearly hear
the fundamental on 7365.

The darned signal sounds different on a clear frequency though, seems
like several of us mis-id it as the MSK signal, the similarity simply being
it is a multi-tone signal.

Mystery solved. No Bulgarians involved.

Thanks Martin.

Tom

>Tom,
>
>I think you will find that this signal is the Cuban bubble jammer 
>("Havana Gurgle"), usually directed against Radio Marti.
>
>On 18090.0 kHz (center freq) the tone bursts are 300 Hz apart, 
>ranging from 1200 to 3300 hertz in each sideband.  It is the third 
>harmonic of the jammers (almost always more than one transmitter) on 
>6030 kHz used by Radio Marti.  This third harmonic is a familiar 
>"friend" of Amateurs using the 17 m band and is frequently reported 
>as an intruder (which it certainly is).
>
>I just listened to the one on 14730.0 kHz (center freq) and found 
>tone bursts from 800 to 2200 hertz, indicating a probable second 
>harmonic.  Sure enough, the fundamental is on 7365 kHz (though I 
>don't know who the target is).
>
>At the fundamental, the tone burst frequencies are separated by 100 
>hertz and range from 400 to 1100 hertz.  From any one transmitter 
>the tone burst period is around 88 milliseconds, although with more 
>than one transmitter active it is difficult to see any consistent 
>period.  Some "intruder watch" monitors have suggested that each 
>sideband is identical, that is a tone is transmitted in both 
>sidebands at the same time, although I have not been able to test 
>this myself.
>
>If memory serves me right, the signal was first reported on 18090 
>during summer 1998 and by early 1999 was being reported regularly. 
>The Cuban government has ignored all requests to fix the harmonic 
>radiation, creating great embarrassment for Cuban Amateur Radio 
>operators.  The jamming transmitters were reported to have been 
>built in China and it is possible that they are not easily modified. 
>We seem stuck with the problem for as long as the Castro government 
>chooses to jam Radio Marti.
>
>73,
>... Martin    VE3OAT
>
>http://www.storm.ca/~iarumsr2/
>