Random bursts

[WrongwayCorrigan]

I have been observing these random bursts that occur on various frequencies. Is this at all related to the noise used by jammers?

Receiver: Grundig G6 Aviator
Anntenna: Telescoping Rod
Place of Reception: Northeastern United States
Date: 07/25/2010
Time: 0324 UTC
Frequency: 7540 kHz

http://www.zshare.net/audio/78673782ffa85a9c/

[SW-J]

I have been observing these random bursts that occur on various frequencies. Is this at all related to the noise used by jammers?

Receiver: Grundig G6 Aviator
Anntenna: Telescoping Rod
Place of Reception: Northeastern United States
Date: 07/25/2010
Time: 0324 UTC
Frequency: 7540 kHz

http://www.zshare.net/audio/78673782ffa85a9c/

RADAR - perhaps the Ionospheric RADAR used to observe the aurora over the poles, but it's not comms and not jamming ...

If you notice, those are sweeps, sometimes slow, sometimes medium in speed and some times rapid. Watching the Winradio WR-G303e display on the PC they are about 15 to 20 kHz wide ...

A number of Google hits result from HF Auroral RADAR:

http://www.google.com/search?hl=en&client=opera&hs=r47&rls=en&q=aurora+radar+HF&aq=f&aqi=&aql=&oq=&gs_rfai=

SuperDARN - showing the scanned areas: http://superdarn.jhuapl.edu/

Wkipedia: http://en.wikipedia.org/wiki/Super_Dual_Auroral_Radar_Network


Extracted from this document:

   http://ursi-test.intec.ugent.be/files/URSIGA08/papers/G05ap3.pdf

the SuperDARN Aurora RADAR network:

 

[Seamus]

Now THOSE are what I'm used to hearing!

Up until a couple of months ago, I could hardly tune the 6900s without hearing those things everywhere, from a slow "whoop-whoop-whoop", to a fast "brzbrzbrbrzbrz!"  They are often (usually?) prefaced by a trio of beeps, and can come singly or in clusters of different speeds.  On occasion, I have heard a whole series of them in increasing speed, one right after the other.

I figured that it was OTH radar, especially since my wire tends towards a north-south pattern, and they frequently swamp reception of other signals completely, so I figured that they had a ton of power behind them.

I have noticed a dropoff in these buzzes/sweeps at my QTH, however.  I assume that they're still going on, but at different frequencies owing to seasonal changes in the ionosphere.  Either that, or those same changes have altered the skip zone so that I'm now in a null instead.

[Seamus]

The sound from 0:45 to 1:02 in [this video clip] is what I get (got) booming in here all the time.  The super-slow one at the end of his recording is new to me.  Most of the time it would just be clusters of two to four different speeds, sometimes just one at a time, and rarely a "full diagnostic run" of every flavor that they had from one end to the other.

[SW-J]

The sound from 0:45 to 1:02 in [this video clip] is what I get (got) booming in here all the time.  The super-slow one at the end of his recording is new to me.  Most of the time it would just be clusters of two to four different speeds, sometimes just one at a time, and rarely a "full diagnostic run" of every flavor that they had from one end to the other.

That last one is a new one on me ... I'm thinking it's the product of something else other that RADAR ...

I had not in recent memory heard the slowest rate of the 'sweeper' ... that was quite a set of sweeps that was captured ...