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Author Topic: 6698.98 KHz New Slow Dasher?  (Read 1485 times)

Offline Teotwaki

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6698.98 KHz New Slow Dasher?
« on: November 28, 2021, 1708 UTC »
Discovered this while on the KFS Omi SDR. It has a roughly 30 second cycle: 27 seconds of silence and a 3 second dash.
Jim
NRD-525, Elecraft KX3 and Elecraft PX3 Spectrum Display
76' end fed long wire & 66' off-center fed dipole for 10/20/40 meters
Orange County, SoCal, The better half

Offline Token

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Re: 6698.98 KHz New Slow Dasher?
« Reply #1 on: November 28, 2021, 1733 UTC »
Discovered this while on the KFS Omi SDR. It has a roughly 30 second cycle: 27 seconds of silence and a 3 second dash.

This is a signal I call, in my Log Books, Long Dashes.  I have logs of this signal going back at least to 2013. 

6699 kHz is a common frequency for Long Dashes, however it shifts around.  If you look around you will find it on more than one frequency at a time, it is common for it to be up on 5 frequencies, one near 6500 or 6700 kHz, one near 8800 or 9000 kHz, one near 12000 kHz, one near 12500 kHz, and one near 16200 kHz.  It sequences these frequencies, high to low, hitting each one every 27 seconds.

This morning it started on 6699 kHz at 1420 UTC.  It was also on 8999, 11938, 12492, and 16192 at the same time.  As I write this (1725 UTC) it is still active on 6699, 8999, 11938, 12492, and 16192 kHz.  Prior to 1420 UTC it was on a different set of frequencies. 

In the current version of this signal (in the past it has had different pulse lengths and cycle times) it is a 2.9 second long pulse every 27 seconds.  The total cycle time is 27 seconds, not 30.  If you look closely at the pulses you will see the first ~200 msec of the pulse has a modulation on it.  Sometimes it has other features also.

I do not know the source, based on propagation I suspect China or the Pacific region.  For a while I thought western China, but now I am less sure.

I have done a couple of videos on this signal on my YouTube channel, here is one I did last year:
https://www.youtube.com/watch?v=vA9-F1-EQOg

I suspect it is a propagation tool of some kind, but more than that I have no clue.  It does not appear to run 24 hours a day.  It is wide ranging, I hear it on EU remotes, Asian/Pacific remotes, and here at the house all at the same time.  Naturally not all frequencies may be heard at the same time in all locations, but generally, if the signal is active, one or more can be heard anywhere.

Right now (1735z, EU after sundown) on EU remotes the 16192 signal has faded to gone in most places, 12492 is getting weak, 11938 is usable, 8999 and 6699 are strong.  Here at the house 6699 is just about gone and 8999 is weak, they were both strong here 2 hours ago.  11938 is usable, 12492 is not quite as strong, and 16192 I would not see if I did not know it was there.  This (both EU signal levels and mine) is consistent with Asian / Pacific propagation.

(edit)  Long Dashes left the 6699, 8999, 11938, 12492, 16192 kHz set of freqs at 1847z and moved to a new set at 1849z, the new frequencies are 6470, 8990, 11920, and 12494 kHz.  I assume the 16xxx kHz freq is either covered by another signal or propagation is keeping me from finding it.

T!
« Last Edit: November 28, 2021, 1859 UTC by Token »
T!
Mojave Desert, California USA

Offline Teotwaki

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Re: 6698.98 KHz New Slow Dasher?
« Reply #2 on: November 28, 2021, 2329 UTC »
Token - thanks for posting a direct link to the video. You've create so many videos over the years that
it would be hard to easily find just one.  :)
Jim
NRD-525, Elecraft KX3 and Elecraft PX3 Spectrum Display
76' end fed long wire & 66' off-center fed dipole for 10/20/40 meters
Orange County, SoCal, The better half

Heathkit

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Re: 6698.98 KHz New Slow Dasher?
« Reply #3 on: December 15, 2021, 0022 UTC »
Hearing a slow dasher on KPH at 0015Z, 6779.58.

Isn't on the LWCA list of Canadian "In Between FER's", so a possible PiFER.

73's

Offline Teotwaki

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Re: 6698.98 KHz New Slow Dasher?
« Reply #4 on: January 06, 2022, 1733 UTC »
it's back. Hearing it on KFS SE right now
Jim
NRD-525, Elecraft KX3 and Elecraft PX3 Spectrum Display
76' end fed long wire & 66' off-center fed dipole for 10/20/40 meters
Orange County, SoCal, The better half

 

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