Unusual pulsing signal on 14.320 MHz


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Message boards : Science (non-SETI) : Unusual pulsing signal on 14.320 MHz

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Michael Watson
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Message 1197915 - Posted: 20 Feb 2012, 18:34:39 UTC - in response to Message 1197553.

Interesting. It's been a very long time since my radio days in the army, so forgive any ignorance I show.

Have you checked for harmonics?
Thanks for your response. Many of the amateur radio bands are harmonically related. A first harmonic of 14.320 MHz would appear in the amateur 10 meter band, at 28.640. If 14.320 is itself a harmonic of a lower frequency it could be 7.160 or 3.580 MHz in the amateur 40 and 80 meter bands, respectively. The problems of non-identification and unknown signal format would remain. One non-amateur frequency might be involved-- 4.773 MHz ( 14.320 divided by 3), which is assigned to the fixed and mobile 'utility' service. This signifies anything other than broadcast or amateur radio. Some obscure or even experimental mode might be under test on such a frequency. I've listened there, but have heard only the familiar 'CODAR' ( Coastal Radar) transmissions, used to study ocean currents. These pulsate, but at a rate of ~ 64 per minute, not 50, like the signal I've heard on 14.320. Also, the CODAR pulses are much shorter, and don't consist of discrete audio frequencies, but rapidly shift pitch or 'chirp'. Will listen on all low-order harmonics when the signal is active again, and see if I can turn anything up. Michael

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Message 1197944 - Posted: 20 Feb 2012, 19:25:13 UTC - in response to Message 1197915.

50 Hz. the ac frequency of most of the world.
____________

Michael Watson
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Message 1198491 - Posted: 22 Feb 2012, 15:25:11 UTC - in response to Message 1197944.

50 Hz. the ac frequency of most of the world.
Yes, the pulsations of the signal discussed are ~50 per minute (~0.8 Hz), about 1/60 of the frequency of the electrical power distribution systems in much of the world, especially in the Eastern hemisphere. Also, just about 1 % of the neutral hydrogen line frequency at 1420.405 MHz. Michael

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Message 1198507 - Posted: 22 Feb 2012, 17:08:04 UTC - in response to Message 1198491.

50 Hz. the ac frequency of most of the world.
Yes, the pulsations of the signal discussed are ~50 per minute (~0.8 Hz), about 1/60 of the frequency of the electrical power distribution systems in much of the world, especially in the Eastern hemisphere. Also, just about 1 % of the neutral hydrogen line frequency at 1420.405 MHz. Michael
To clarify the above, it is the reception frequency of 14.320 MHz that is is about 1% that of the hydrogen line. (Actually about 0.9919 %) . Michael

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Message 1198513 - Posted: 22 Feb 2012, 17:27:20 UTC

Cut it be a tracking pulse for lets say a tagged critter (terra or aquatic)? How about a geological or oceanic survey beacon?

Either one of these may be set to transmit during previously programmed times for longetivity reasons...just a thought

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Message 1198519 - Posted: 22 Feb 2012, 17:41:33 UTC

Another possibility - maritime drug runners cud b using it as a connective for a pickup/dropoff location.

Those familiar with SSB in the 80's and early 90's wud hear "Meeee-ra. Meee-ra. Meeeeee-ra - numerous times thoughout the late evenings. These were attested to "commercial" fishermen df'g for illegal drug transfers primarily in the Gulf of Mexico and SE Atlantic.

Michael Watson
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Message 1198669 - Posted: 23 Feb 2012, 1:53:44 UTC

It seems very unlikely that any scientific project would be set up on this particular frequency. It is part of a band allocated to amateur radio, exclusively. There are many other radio frequencies available for scientific work. Smugglers would likely not respect the proprieties of frequency allocations, and might make use of readily available amateur radio equipment. I note, however, that the mysterious signal has been heard, very largely, during daylight hours. This does not seem to match the hours when smugglers would be most likely to operate. In any case, we have to ask ourselves if 20 meters would be a practical band for smugglers to use. It normally has a 'skip zone' within several hundred miles of the transmitter. Within this zone, no signals can be heard at a distance much beyond the line of sight. Probably not too useful in tracking down caches of contraband materials or other vessels. 40 or 80 meters, other amateur radio bands, seem the natural choice. They offer both local and regional coverage, and work particularly well in the latter application, at night. 80 meters in particular, lends itself to to radio direction finding, so as to be able to move toward, and find, a radio-marked objective.

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Message 1198703 - Posted: 23 Feb 2012, 3:39:07 UTC - in response to Message 1190994.

I'm curious. You say the audio tones are at "about" 500 and 1000 hz. Anyone have the equipment to confirm "exactly" what audio frequencies are being modulated? I've an idea of what it might be, or might be related to. But I don't want to throw my two cents in without knowing the exact audio frequencies being xmited, for fear my ignorance may be discovered. :)
-Carl

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Message 1198820 - Posted: 23 Feb 2012, 15:59:32 UTC - in response to Message 1198703.

I'm curious. You say the audio tones are at "about" 500 and 1000 hz. Anyone have the equipment to confirm "exactly" what audio frequencies are being modulated? I've an idea of what it might be, or might be related to. But I don't want to throw my two cents in without knowing the exact audio frequencies being xmited, for fear my ignorance may be discovered. :)
-Carl
The audio frequency figures were estimates, apparently by ear. Not mine, but from a ham on the East coast who was able to hear the signal. I suspect he has a better 'ear' than I do! The next time the signal appears, I'll try various tones on an audio signal generator until I get a match. I wouldn't worry about having my ignorance exposed. I honestly find that I learn the most when this happens. Who knows, you might be right and solve this thing for us. Supposing the tones are exactly 500 and 1000 Hz, what is your proposed explanation for the signal?

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Message 1198925 - Posted: 23 Feb 2012, 18:53:04 UTC - in response to Message 1198820.

If any direction finding can be done on the signal from the U.S. west coast, I am expecting the signal to be coming from 220 degrees to 340 degrees. DF'd about 30 minutes apart, I expect it not to DF the same compass direction twice. I'm also expecting the frequency of the tones to have a difference of 268 Hz or more.

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Message 1198963 - Posted: 23 Feb 2012, 20:18:47 UTC - in response to Message 1198925.

Maybe he's picking up Willy the whale's signal.

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Message 1198967 - Posted: 23 Feb 2012, 20:29:34 UTC - in response to Message 1198963.

Nope. It's definitely not anything nautical. In my previous post I mentioned DF'ing it fron the west coast. I meant east coast, and it'll DF anywhere from 220 degrees to 330 degrees. Also if DF'd twice 30 minutes apart, I expect a difference of at least 10 degrees; probably closer to 20-25 degrees. Hopefully, someone can provide this info plus the info requested in my previous post. It may or may not confirm my hypothesis.

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Message 1199027 - Posted: 23 Feb 2012, 22:27:07 UTC - in response to Message 1198967.
Last modified: 23 Feb 2012, 22:33:43 UTC

Nope. It's definitely not anything nautical. In my previous post I mentioned DF'ing it fron the west coast. I meant east coast, and it'll DF anywhere from 220 degrees to 330 degrees. Also if DF'd twice 30 minutes apart, I expect a difference of at least 10 degrees; probably closer to 20-25 degrees. Hopefully, someone can provide this info plus the info requested in my previous post. It may or may not confirm my hypothesis.
Anything shifting position that rapidly would either have to be very nearby or moving at extreme speeds. Much beyond the line of sight, the nearest it could be is on the order of several hundred miles, due to the way 20 meter signals propagate. The signal fades in and out, suggesting propagation by ionospheric refraction, and a distance at least that great. The directional bearings given indicate a route inland from the East coast. I'll do my best to provide the requested information. I've had some people propose to do radio direction finding, but haven't heard back from them. Michael

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Message 1199083 - Posted: 24 Feb 2012, 0:59:21 UTC - in response to Message 1199057.

At this time, I'm not looking to identify the signal per-se, or any intelligence it may or may not be carrying. I'm looking at identifying the source of the signal. If the signal can be DF'd from the west coast of the US, then I expect it to not be locatable from the west coast, as on a DF scope it will appear to be coming from all directions. That is, if my hypothesis is anywhere close to being correct. It's probably not. But then I kinda like the old addage of "If you can't prove what it is, then confirm what it is not so you don't waste time on what isn't there".

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Message 1199881 - Posted: 26 Feb 2012, 4:57:04 UTC

It's been 3 days. Nobody got any followup on this signal yet? I've been listening on US east coast receivers via globaltuners.con when I can. But during the timeframes mentioned I've not been able to tune to 14.320Mhz. So have been listening during evening hours when rcvrs are available for me to tune. There are no rcvrs on the west coast on globaltuners. So I can't check that side of the US. So I checked out a rcvr in Hong Kong and was able to listen for a whole 5 mins. I "think" I heard it weak, around 0400GMT, but it was so weak, it very well could have been my imagination pulling it out of the noise. I still need some kind of DF on it before I give my hypothesis though.

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Message 1200121 - Posted: 26 Feb 2012, 19:53:05 UTC

To the best of my knowledge, the signal wasn't active during the past three days. I managed to hear it from about 17:40 to 18:50 Universal Time this morning. This is the first time I've heard it in 12 days, after a great deal of listening for it. It was too weak and fading to do even rough direction finding, or check the exact frequencies of the audio tones. I was glad to hear it at all, after this long absence. I hated to think it had disappeared for good without any explanation for it, and after I'd tried to draw people's attention to it. The signal may have gone back to its original pattern of being heard from 16:00 to 23:30 U.T., but I will listen at various other times, too, and see what I can hear. I'm sure it was the same signal. It had the same odd characteristics. 50 pulses per minute, in groups of 37 in one tone, followed by 37 in a lower or higher one. The last pulse in each group shorter than the rest. A slight pause between each group of 37. Fading in and out, as is typical of weak, high frequency signals coming in from a considerable distance. Michael

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Message 1200209 - Posted: 27 Feb 2012, 0:50:33 UTC - in response to Message 1200121.

I've been trying to hear it for hours now, but was unable to get an available rcvr on global tuners until 0030GMT. Checked a few on the east coast, one in Phoenix, then Hong Kong and a few in western Europe. No can hear it. Guess I'll just keep trying tomorrow and/or hope a hammer out there will hear and report here on it.

Michael Watson
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Message 1200221 - Posted: 27 Feb 2012, 1:47:23 UTC
Last modified: 27 Feb 2012, 1:51:36 UTC

Heard the signal again this afternoon, from 00:36 to about 01:30 UT. Very weak for the most part, up to S. 2 (1 bar) occasionally. The signal has been up to S. 9 (4 bars) in the past. Without knowing the antenna arrangements of these online receivers, its hard to say why you didn't hear the signal on any of them. Michael

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Message 1200228 - Posted: 27 Feb 2012, 2:17:28 UTC - in response to Message 1200221.

when I first tune the receiver, it's usually in the 2-meter band when I get to it. So when I pop down to the 20 meter band, I can't here it because I can't change the antenna.

Michael Watson
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Message 1200452 - Posted: 27 Feb 2012, 21:22:11 UTC

Signal heard from 20:43 today. Still heard as I type this at 21:21 UT. Fading in and out a good deal, and not particularly strong; up to S. 2 (1 bar). An online receiver specializing in the High Frequency range would probably have an antenna of reasonable efficiency at 20 meters. My own antenna is a low, multi-dipole, covering most H.F. bands I find this brings in less electrical noise than a random length wire. Michael

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Message boards : Science (non-SETI) : Unusual pulsing signal on 14.320 MHz

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