Travelling HF signal - oddity?

[Digital]

I'm having a nosey around HF this evening. At 1934 UTC an odd signal made an appearance. It travelled right the way through an entire MHz, in one end and out the other. You can see it faintly on the screen shot I've attached. That was around 11 MHz.

Then later, I was around 4 MHz and the same signal appeared again - so I followed it and tracked it again into 11 MHz! Something is sending a signal zooming across huge expanses of the spectrum this evening, and I've not seen its like before. Any thoughts?

I've caught it a couple more times since then as well.

[neil-c]

Do you mean the faint blue line at the very bottom of that screenshot running all the way across the screen?

If so it is something i see regularly using the Pro+, I did put it down to something like local interference such as something switching on or off but it does look like something I quite often get.

[bigpimp347]

i was using the MFJ analyzer today on a Cobweb but doubt the signal would be that great
but i was going from 10mhz upto 60mhz..!!

not sure what you have but i've heard similar things over the years like a signal that comes from bottom upto the top of my radio sometimes fast others like it's a drifting carrier that slowly moves up the band..

maybe it's man-made or could be anything.!

[Digital]

Do you mean the faint blue line at the very bottom of that screenshot running all the way across the screen?

Sorry - I should have been more careful when I cropped the image.
No, that line is where I changed frequency, I think. If you look closely there is a diagonal line tracing the signal as it moves up in frequency and forward in time.

I've attached another image with an arrow to show where it is. It's not as good an image, but you can then find it better on the original image.

Incidentally, I keep seeing the same signal everywhere and every few minutes this evening.

[Adriano9966]

could it be PLA interference???

[Digital]

could it be PLA interference???

I don't think so - this seems to be a single carrier moving quickly up the spectrum. I'm more-or-less in the middle of nowhere here too, so I'm very unlikely to get that kind of interference.

[Digital]

not sure what you have but i've heard similar things over the years like a signal that comes from bottom upto the top of my radio sometimes fast others like it's a drifting carrier that slowly moves up the band..

I've seen similar things below LW, and I know there are naturally occurring signals down into VLF and ELF that look a bit like this. But this must be man-made, it's just hard to think of what a signal like this would be! It's really odd to watch it sweep over the screen!

[crusty]

You see lots of what appear to be alien/new signals when you get into SDR. They've been there all along, but present themselves as a simple 'chirp' in a conventional receiver as they march along the spectrum.
http://www.hfunderground.com/wiki/Ionosonde
ATB.

[Andy]

There is a sweeper signal like that that appears on 4m. It enters the bottom end and quickly moves up and out of the top. Various theories have been put forward, including a harmonic from an rf heater usedin plastic manufacture.
I wonder if yours is some kind of wideband chirp radar?

[Adriano9966]

we have just entered the twilight zone

[neil-c]

You see lots of what appear to be alien/new signals when you get into SDR. They've been there all along, but present themselves as a simple 'chirp' in a conventional receiver as they march along the spectrum.
http://www.hfunderground.com/wiki/Ionosonde
ATB.

I have noticed that quite a lot since I started to use a SDR receiver. All those annoying chirps and squeaks do look a lot more intriguing when you see them on the waterfall function.

[ChrisCSL]

It's an Ionosonde. It measures the 'critical frequency, and sounds like somebody transmitting while spinning the tuning knob very quickly.

Won't bore you, just google it

[StormShadow]

If any of these were alien signals would we even know?

[grahamwilman01]

capt00.jpg

One of the weird noises(sounds like a howling wind starting right down in the noise and building till it peeks and then fades back into the noise) I get on HF especially on 40m metres although I have heard it on the other frequencies as well, many a theory has been banded around the radio club including ground radar from Manchester Airport as I am only +/- 2miles from the start of Runway 2 and they have a Mahoosive radar dish at the start of the Taxi way.

[Black_Pirate]

Military ? If you have a receiver at the other end programed eith
The time,rate and span... You could send code and "listeners"
Would find it difficult to receive and decode given the encryption
Also...
What sdr are you using .... Funcube??