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Author Topic: Possible new radar, 7735, 8050, and 16110 kHz  (Read 1824 times)

Offline Token

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Possible new radar, 7735, 8050, and 16110 kHz
« on: October 27, 2012, 1458 UTC »
A signal was reported in the #wunclub IRC channel on the 25th of October.  It appears to be a new Radar or a previously unreported mode of an existing Radar.  My guess at this point is that it is a new system.

I have seen this signal so far on 3 frequencies, 7735, 8050, and 16110 kHz.  I assume more frequencies will be found as time goes on.  The signal appears to set on one frequency for an extended time, sometimes for hours, before moving on to the next.  So far it has only been seen on one frequency at a time.

The signal appears to be a simple pulsed type Radar.  It has a PRF (Pulse Repetition Frequency) of about 9.1 Hz (110 millisecond PRI, Pulse Repetition Interval).  Although I have not yet gotten a good recording to determine Pulse Width, the PW appears to be about 900 microseconds (based on the spectrum peak to first null measurement of about 1.1 kHz).

So far I have not seen an indication that the system beam steers.

The signal appears to be from Europe or that general area.

This signal is very similar to the old Russian Woodpecker except it has a slightly narrower pulse width and does not appear to use pulse compression.

Spectrogram capture showing PRI of 110 msec here: http://www.pbase.com/token/image/146959548/original.jpg

50 kHz span spectrum capture of the 7735 kHz signal, using Max Hold, shows the general spectrum shape and the peak to null delta: http://www.pbase.com/token/image/146959634/original.jpg

25 kHz span spectrum of the 16110 kHz signal, again using Max Hold, showing the same general peak to null delta, indicating approximately the same pulse width:  http://www.pbase.com/token/image/146968669/original.jpg

Video of the signal on 16110 kHz here, with several different demodulation modes used to show what it sounds like in AM, USB, and CW: http://www.youtube.com/watch?v=GnvwLhu0HOA

Mojave Desert, California, USA
Mojave Desert, California USA