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Author Topic: PIP 6820 kHz 0045 UTC 6 April 2018  (Read 2361 times)

Offline Traveling Wave

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PIP 6820 kHz 0045 UTC 6 April 2018
« on: April 06, 2018, 0047 UTC »
0045 UTC - Strong PIP S9 +20 dB, on 6820 CW mode, sound file attached, on then off, on then off.
0051 UTC - PIP still going strong.
0053 UTC - Four second interval between PIP's.
0104 UTC - PIP still going strong.
0126 UTC - PIP is gone.
« Last Edit: April 06, 2018, 0127 UTC by Traveling Wave »
Location: Western New York ( Niagara Frontier)
Radio :TS480 with RTL-SDR pan-adapter, HDSDR software, Omni-Rig Control, Zenith T/O R600,T600
Antenna: 40m dipole, 20-17-15 meter fan dipole. One of N. Tesla's own prototypes. A high-powered mutant of some kind never even considered for mass production.
Knowledge is a deadly friend when no one sets the rules. The fate of all mankind I see is in the hands of fools - from Epitaph by King Crimson
eQSL appreciated KC2ZYL@gmail.com

Offline Token

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Re: PIP 6820 kHz 0045 UTC 6 April 2018
« Reply #1 on: April 06, 2018, 1440 UTC »
Interesting that this went away for you at 0126z after having been so strong, the network did not go off air until 0141z.  I caught this network last night starting at about 0043z and recorded it until the end, at 0141z.

This is what I call the Pips Network in my logs (I often name signals I see more than once in my logs to assist searches in my database).  A search of these forums for that term will find past posts about the network.  This mystery network of ditters has appeared periodically for several years now (my earliest log is April 2012).  It shows up a few times a year.  I have no real idea what it is for, but I suspect some kind of ionospheric measurement tool.

You heard it on 6820 kHz, but if you had looked around a bit you would have found it on many other freqs as well.  The pulse is (in this case, it uses several different formats) 62.5 msec long with a period of 3.0 seconds.  It cycles up through its frequencies, freq 1, then freq 2, then freq 3, so on until it reaches its last freq and then back to freq 1 to start it all over again.  With the 0.0625 sec x 3.0 sec format this allows up to 48 frequencies.  I only found 38 of the possible 48 in use last night (from 6820 kHz to 17440 kHz), it is possible, even probable, that all 48 were in use but propagation conditions prevented me from finding the remaining 10.  The upper freq Pips were very weak.  With the lower freq Pips as strong as they were I suspect 6820 kHz was the lowest freq in use.

There sometimes are two sources active at the same time, they often share one or two frequencies and on those frequencies you may hear a double Pip with odd timing.  Two frequencies last night (10990 kHz and 12010 kHz) had double Pips however I only found one network active for sure.  It appears the second network may have been only using those two frequencies and no other.

The freqs I had active last night, from 0043z until 0141z, when it turned off:

6820
7570
8400
9050
9900
-*
10200
10350
10510
10670
10830
10990 (double Pip, 2nd Pip is with the other freqs, 1st Pip with 12010 kHz)
11150
11490
11660
11830
12010 (double Pip, 2nd Pip is with the other freqs, 1st Pip with 10990 kHz)
12190
12560
12940
13130
13530
13730
13940
14150
14360
14580
14800
15020
15250
15480
15710
15950
16190
16430
16680
16930
17180
17440

A couple of things to note:

The "-*" entry I made indicates that based on pulse timing there should be a frequency there, something between 9900 kHz and 10200 kHz.  I found nothing between them, but the Pips may have been covered by another signal in that range, several other freqs were under other signals and I had to look very close to find them.

This signal often uses frequency sets, or combinations of frequency sets, it has shown before, but I have not logged this freq set in use before.  Some of the freqs are in my logs, for example 9050 kHz and 11150 kHz are common freqs, others I have not seen before.  I have not been as active in the past year or so as in years past though, so they may have been using this for some time and I just missed it.

10990 kHz and 12010 kHz showed double Pips.  The second Pip on each of those freqs was in sequence with the other freqs found, i.e. the timing showed there was a probable relationship with the other freqs.  However the first Pip on each of those freqs was not in sequence with the other freqs, but was in sequence with each other.  SO while it looked like there should be two networks (sets of freqs) active (as there often is) the only freqs I could find with that second network signal were 10990 and 12010 kHz.


T!
« Last Edit: April 06, 2018, 1450 UTC by Token »
T!
Mojave Desert, California USA

Offline Traveling Wave

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Re: PIP 6820 kHz 0045 UTC 6 April 2018
« Reply #2 on: April 06, 2018, 1547 UTC »
Token, thanks for the reply. I was monitoring the SW pirates last nite when I noticed the PIP.
I made note of the frequencies you listed and next time I see a PIP I will start checking the list. :)
Location: Western New York ( Niagara Frontier)
Radio :TS480 with RTL-SDR pan-adapter, HDSDR software, Omni-Rig Control, Zenith T/O R600,T600
Antenna: 40m dipole, 20-17-15 meter fan dipole. One of N. Tesla's own prototypes. A high-powered mutant of some kind never even considered for mass production.
Knowledge is a deadly friend when no one sets the rules. The fate of all mankind I see is in the hands of fools - from Epitaph by King Crimson
eQSL appreciated KC2ZYL@gmail.com

Offline Token

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Re: PIP 6820 kHz 0045 UTC 6 April 2018
« Reply #3 on: April 06, 2018, 2342 UTC »
On further review, this is not a new set of frequencies, rather it is the same set, or almost the same, of freqs used the very first few times I logged this signal, back in April of 2012.

T!
T!
Mojave Desert, California USA

Offline Josh

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Re: PIP 6820 kHz 0045 UTC 6 April 2018
« Reply #4 on: April 07, 2018, 1740 UTC »
Suppose it's a prop beacon?
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Offline Token

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Re: PIP 6820 kHz 0045 UTC 6 April 2018
« Reply #5 on: April 08, 2018, 1700 UTC »
Suppose it's a prop beacon?

I can't really see that as the application, the system shows up too infrequently to very useful as a propagation beacon set.  I mean, unless you only want to check propagation every few months or so at irregular intervals and on varying frequency sets.

T!
T!
Mojave Desert, California USA

Offline Token

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Re: PIP 6820 kHz 0045 UTC 6 April 2018
« Reply #6 on: April 08, 2018, 1702 UTC »
Some pictures of a couple of these freqs.

This first picture is an audio histogram of the Pips on 10670 kHz.  The radio is tuned to 10669 kHz USB mode to produce the Pips at 1 kHz.  62.5 msec long Pips once every 3.0 seconds on this, and all, freqs.


The next picture is the same setup, but looking at the Pips on the next higher active frequency, 10830 kHz.  Again tuned 1 kHz low to make 1 kHz audio on the Pips.


This next picture is both of the above frequencies, showing the relative timing of the two frequencies.  The radio is tuned to 10669 kHz USB for the 10670 kHz Pip, making 1 kHz audio, and 10828.9 kHz USB for the 10830 kHz Pip, making 1.1 kHz audio.  You can see that the next frequency starts as soon as the Pip on the previous frequency stops.


Here are the double Pips on 10990 kHz.  Again, tuned 1 kHz low and in USB mode to make 1 kHz audio.


Here are the double Pips on 12010 kHz, note the gap is different than on the 10990 kHz double Pip freq.  This is caused by there being two networks in use, and differing numbers of freqs for each network between 10990 kHz and 12010 kHz.


T!
T!
Mojave Desert, California USA

 

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