Anybody recognize this noise?

Gary L. Robinson

I get this noise on 17mtrs - I don't see it any other ham band or any place I have looked at on the panadapter.  It is about S6 signal strength and at times shifts up and down sometimes as much as 40-60 khz -- maybe more.

I have not tried to shut off everything in the house and run on battery yet but have seen this noise ever since I got my 6400.  Prior to getting the 6400 though I seldom used 17mtrs.



I am heading for bed but will check tomorrow and see if anyone has any ideas what this might be.

---Gary WB8ROL

[Deleted User]

I've got a  similar to that on 80m here in New England

Craig Williams

The **** in gain is your antennas bandwidth. Short your antenna or disconnect it and it should go flat. Should see this on other bands also.

K5CG

Or your tuner.

Gary L. Robinson

No, it's not the antennas' bandwidth.  The noise changes frequency at times both up and down several khz without doing anything but watching it.  Antenna bandwidth is plainly seen when I widen the bandwidth of the slice and it is a more gradual curve.  At a slice 7mhz wide I see nothing else that remotely looks like that noise and I can see the bandwidth curves for the antenna.   I can also rotate my beam antenna and null out the noise when pointed due south.  And I have tried several other antennas and see the same noise.  This is the ONLY band I see it on and I suspect man made noise but not sure where or how it is being generated.

James Whiteway

Had something similar with a neighbors failing A/C system. Why it was only showing up on 20 meters I have no clue. But, that was the only place it showed and only when the unit was running. Once it finally died, it went away. Thankfully, they have a new unit and it's quiet
.james
WD5GWY

VK7WH Winston

Can you show us both the panadaptor and the waterfall display, as the waterfall might give further clues

Gary L. Robinson

I'll do another screen capture with both panadapter and and post it later.  In a ragchew right now ....

---Gary

Gary L. Robinson

Here is a screen shot of the noise with the panadapter and the waterfall.  It sounds like a rough electrical noise of sorts.  And it moves back and forth occasionally but keeps basically the same or similar width.



---Gary WB8ROL

Gary L. Robinson

Hmmmm.  I will check my own old failing A/C system when I can turn it off.  If I tried that right now I would not win any points with the XYL who is asleep running the A/C in the bedroom hihi

VK7WH Winston

Thanks Gary. I can't recall seeing anything like this before., although it sure looks local. Certainly worth switching the AC off when the time is right. Winston

Gary L. Robinson

Well, it's not local in the house - turned everything off and still saw it this afternoon.  But I think it is local to the small village I am in or not too far away.  I may in the future borrow my brother's FM handheld (forget model) that also covers HF bands for RX.  It's a great tool for tracking noises hihi

---Gary WB8ROL