swishing stations

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I have noticed some signals which seems to swish up and down the bands and it looks like a carrier that moves along the waterfall. Does anyone know what these are are what radios can do this type of tuning.
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John

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Posted 3 years ago

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Walt - KZ1F

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I've been hearing them since I was first licensed in 82. It is only since I bought the 1500 and, later, the 6000 that now I can see them. Some say it's radar. I am sure some think it's the government spying on us. I think it is a kid screwing around with his dad's radio.
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Jon - KJ8S

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John

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I think these stations are amateur or perhaps military. Those who have never seen them, just look carefully on your waterfall display and you will see what appears to be moving red carriers which most times move very fast across the band, but then also move very slowly and even stop on stations who are in a qso, and the carrier disappears. Its quite easy to see.
(Edited)
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Jon - KJ8S

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From your description, it doesn't sound like an Ionosonde to me.  I've followed Ionosondes for 10+ MHz by dragging the waterfall to keep it in view.  They seem to always change frequency at a constant rate and eventually will either fade out or come to an abrupt halt.

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Larry - W8LLL

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I have heard them since the 70's before I could actually see them on a water fall and they are doing what I always imagined. Zoom way out on your pan adapter and you will see them whipping though many bands.
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Walt - KZ1F

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Interesting Larry, that seems to eliminate the kid messing with his dad's rig.
John, yes, I've seen them too, that roll like an ocean swell (a wave but no crest) and then stop on a qso. Actually, I don't recall noticing the waterfall image of it, simply the pan image which resembles an ocean swell, whether it stops or just rolls through the pan. This is interesting!

This, however, is not what I was referring to. What I see is a modulated signal, not a pulse, or chirp.
(Edited)
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John

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Its not the same thing I am talking about Walt. I will try and make a short video clip of it.
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Ken - NM9P, Elmer

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There is no 'it' explanation. There are many different types of sweeping signals. Each has its own unique pattern. Some are ionosondes. Others are different research tools. Others are probably hams sweeping their VFO's to check their SWR. Others are just hams messing around. Others are unknown....
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Barry Jablonski

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It also could be CODAR (on east coast of the USA)...

Barry
WB2ZXJ
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K1FR

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Am seeing the same thing here (northern VA) tonight.  Definitely appears to be CODAR, and I am hearing/seeing 5 separate signals between 4.5 to 4.8 MHz.  Some weak, some up to S8.  Had never heard of CODAR until this thread.  Very interesting!  Always learning on this site.

73, Tom
K1FR
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Barry Jablonski

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Hi Tom,

The CODAR signals are weak tonight -- here is a screen shot from around 4.775 MHz this evening in NJ.  Interesting stuff...

Barry
WB2ZXJ
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John

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Off on college run shortly, but will get some images later today. What I am seeeing looks like a moving carrier
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Kevin WB4AIO

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CODAR and SWR tweakers certainly explain some sweeps we hear on HF.

But one mystery remains. As others have mentioned here, I've been hearing it for many years -- since the early 1970s. It manifests as a slowly moving carrier -- maybe a kHz every five or ten seconds -- that is not very pure or stable. It sounds, for lack of an exact term, "wobbly" -- though it does have a definite direction to its drift. Typically, it wanders many dozens of kHz before "winking out" and re-starting on the other edge of its range. I've heard these wobbly carriers from 80 through 20 meters.

When I first saw them, I suspected they were local phenomena, but then I discovered that people hundreds of miles away from me could hear them too.

Maybe it is significant that when I lived in the Washington, DC area -- from the 70s through 1991 -- I could hear some of these mystery carriers during full noontime daylight on days when propagation was literally limited to a couple hundred miles at most.

73,

Kevin, WB4AIO.
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John

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I think a lot of our problems this side is the EU and what we call the zoo. There are a lot of stations jamming each other any anyone they dont happen to like for what ever reason. Some are ex eastern bloc countries jamming the USSR and then we have north africa thrown in as well. I still remember my days in south africa, were it was dead quiet most of the time.

I am on 17m right now, but no swishers so far. Hope to get some video footage later on 40m. The flex software along with my trust Dantong FL3 audio tracking notch filter, does a good job and believe me, I have used it in anger many times.
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Dave KD5FX

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I've got a 'smart' battery charger for my car that does this. I KNOW it's this charger because I put an X10 remote on/off control on it. When I see a sweep or other interference on the Flex, I hit the 'off' and the problem disappears!

I've also seen strange sweeping types of interference from switching power supplies in the house that power small radios, flashlight chargers, etc. These days, just about ANY 'wall wart' is probably a switching power supply and can be the source of interference!

I bought a new SWR/Power meter from Ameritron at Dayton. It came with a small little 12 VDC SWITCHING power supply to power the LED lights! And yes, I could see the slight noise it makes on 20 meters! So, I wired up the meter directly to my Astron NON-switching supply, problem solved!

By the way, if you are powering ANYTHING in the shack with a switching power supply you should run some tests. I used to have one of the MFJ switching supplies, the QST review said it was one of the quietest available (interference wise). Well, I ran some tests by putting the Flex on a 12 V battery and plugging in/out the MFJ power supply. I could see birdies on almost EVERY band appear and disappear as I turned it on and off. Needless to say I got rid of it and went back to a Astron Linear power supply.
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Dale KB5VE

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There was a presentation on the today show last year talking about power consumption in the house. The highlight of this was the number of wall warts we have in a house and they p,lintel out how much electricity is used each year by these which are plugged in with no thing attached and how it was still using electricity even without the charging device attached. Said to feel of it and if warm it was costing you. They also touched on the interference they generated. To radios and ts. I went through my house and found we had 23 wall warts plugged in. I then disconnected from item it was attached to for 24 hours and went to each checking to see which one was warm . I found 16 were drawing current even though nothing was attached to it. Several of these were putting off a low level noise within the ham bands. I then decided when possible I would put a smarty linear power supply to power items and chargers. Thanks to ham fest flea markets I came up with eight nice 2.5 to 5 amp power supplies. Grouping items that required charging in groups I was able to do away with 3/4 this of these walwarts. And be aware all walwarts are bad there are some quality ones out there. I did see a small decrease in noise but I figure the cost of these supplies , less than $6 each ( I just cut the cables off walwarts, ) will be paid back in one year.
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John

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Oh yes, I have been doing this for a long time now but a lot of people seems to like the idea of leaving them plugged in for some reason or other. They do generate a lot of noise but low levels and it will only affect the radios if its in the same room I would think. Another problem child is these new led light bulbs and not forgetting the low energy one's. Stand next to them with a portable sw radio and see what noise they generate. Central heating and thermostats are another pain in the butt as are plasma tv's.
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John

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I have done my own tests to prove its not locally in the house by running on batteries with the house supply switched off. The trick now is to catch these swishers in the act, as they are ellusive most of the time.
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Simon 2E0XZZ

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I'v heard and seen the fast carriers chasing up and down the bands, I put it down to radio amateurs testing antennas with antenna analizers they give out very small variable qrp signals that can propagate some distances
I to have a antenna analizer unplug the antenna pl plug to radio to decensitize and test the antenna and you will hear the carrier chasing up and down the band as you test
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John

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I still cannot conclude that these are people tuning their antennas, as they dont act like someone do this. Anyway we now have a commercial station on 7.2 which is spreading right down to .185
If any Uk stations can send a report to our intruder watch, they will appreciate it, especially  if its causing problems with qso's.
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Robert AA6UP

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Not to change the subject, but did anyone else see/hear the signal on 6998 KHz last night (6/25)? It was about 6 or 7 KHz wide and was a couple KHz inside 40M. I have never heard one like it before and consisted of what sounded like data with each transmission lasting between 2 and 7 or 8 seconds. I've been on the air since 1958 and this was a completely new one for me. It didn't sound like any of the current data formats.
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John

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I managed to record a video clip showing the one swisher I saw. Its in at about 1min 23sec of the video. Its an avi file so quite big. I am down with morphine right now, so not able to fix the video file etc.
https://www.dropbox.com/s/pmiffh9w8pfufre/swish1.avi?dl=0