Interesting Pan and Waterfall - Anyone else have this?

K7JV

Since my FLEX-6400 arrived at our home, I've been seeing what appears to be significant harmonic signals across nearly all of the HF spectrum.  It appears to start a bit above the AM broadcast band.  I have a pretty extensive spreadsheet where I noted the spike frequencies and tried finding a common denominator for them, and it appears that repeat frequency is slightly less than 33 kHz.  In some segments of the band the spikes will be slightly less than 66 kHz apart, or half the frequency of the majority of the spectrum.  Very interesting.

I just now tried turning off every breaker in our home except the one that powers the radio, and found virtually zero change by de-energizing them one at a time, or even with all off except for the one that feeds the FLEX station.

I am just curious whether any others have had a similar experience, and if so, if any cause was found for it.  I'm not sure that I expect to find a solution, easy or hard, but it's worth asking the question.

Cheers to all!

      Jim, K7JV

Erika - KØDD

Same here, same repetition.

K7JV

Interesting note:  Hams with standard radios would never know that this sort of thing is even going on.  Without a panadapter and/or waterfall like we have on the FLEX systems, phenomena like this is just out of sight and out of mind.  These radios really are pretty amazing!

K7JV

Wow, interesting.  I wonder what is generating it.  My station is in SW Idaho, in a suburb of Boise.  And it is strong across nearly all bands, pretty much regardless of propagation conditions.

Erika - KØDD

Does it go away if you remove the antenna?

K7JV

Yes, it goes totally flat.  Thankfully!  At least it isn't radio-generated or power supply generated, at least on the 12 volt side.  :-)

Mike Smoot

Try temporarily eliminating your power supply from the configuration.  If possible, power your Flex from a 12V battery long enough to look for a change in symptoms.  I once had a Radio Shack 28A DC switching supply that generated spurs over the HF spectrum, giving similar-looking results on the panadapter.

Erika - KØDD

I "See it" mostly across the 80 meter band.  I can't remember if I went higher or not.

It is was very irritating.  The thing here has a center carrier with maybe two or three side band carriers lower in signal strength.  It could be an IMAGE received from something external, It could be a remnant from you digital Power Meter (PLC) or a digital (PLC) off your water heater...  I have a both of those here.  Its probably super nasty with a lot of spurs....  **** up your water meter or shoot into you power meter giggle...  Of course it could be something else...  But I suspect it's you utility company and mine trying to drive us nuts. 

Erika - KØDD

I meant to say water meter our Utility does drive by meter reading every month.

Dave Skinner

I have it here in Louisiana In my case I have Dish satellite TV and it is caused by the DVR. As you said, without the Flex 6500 I wouldn't know it is there. Dave. WA5IMF

KD0RC

Looks a bit like switching power supply noise to me, but it could be a tv or computer monitor too . One trick to narrow it down is to put a six inch or so loop of wire at the end of a piece of small diameter coax like RG58. Make sure the coax is long enough, then put the loop next to every piece of electronic gear in your shack while watching the panadapter. I have found some unlikely culprits that way. If you have a long enough piece of coax, you can scope more of the house, or even get it near you neighbor's houses to see what is going on. 73, Len, KD0RC

Stephen Linton

could it be solar panels?  i get it every 32khz from the house next door.it goes away at night    good luck.

K7JV

Ok, sorry for the delay.  I put the entire FLEX radio on a battery and turned off the entire incoming power to our home.  So NOTHING was powered except the 6400 and the Maestro, and they were powered directly from a battery.  There was no noticeable difference between the displays of the radio on the battery and zero house power, and normal house power and the Powerwerx switching power supply that I normally use. 

I actually thought that might be suspect, until I saw zero spikes and a flat panadapter with the antenna disconnected.

We do not have any solar installations in our townhome development, so that's not it.

Our electrical supply is underground with current technology equipment and installation and is not likely a source for anything like what I'm seeing.

I really do feel like I've eliminated anything in the house as being a source of the spurious signals.

KD0RC

One clue is "townhome".  Surveillance cameras can be very problematic and are often deployed in common areas of townhomes.  If you have a portable receiver, you may be able to implicate or clear cameras as a source of noise. A loop antenna on a stick can be a good way to check individual cameras.

Also, if you share a wall with a neighbor, you may be able to "see" the source through the wall using a small loop.

Len

Mark_WS7M

That looks kinda bad.

I also notice your noise level is S7, at least where you have the current slice.  With the bands the way they are these days I am not sure you will hear anyone with that noise level.

You didn't mention what your antenna was.  If it is a vertical they are very noisy on receive.  You might try a dipole and see if it gets any better.  I doubt the spikes will go but maybe the noise level will decrease.

My noise level on 40m is like S2 on a day with Thunderstorms it goes to about S4 to S5.

But on 20m I do have a big noise spike at 14.030 and my buddy across town with a IC7300 sees it as well so it is something in town I think.

K7JV

You all are awesome!  New information.  My test was very thorough, but I failed to think of one item that turned out to be a culprit.  I forgot about my UPS that powers (You nailed it, Len), our RING cameras.  We have six of those.  The spurs from the cameras do not, however, add a lot of spikes to the panadapter image.  Between about 6.9 MHz and 7.6 MHz the cameras added eight significant spikes.  Unfortunately they were not regularly spaced so they are separate from the evenly spaced spikes I'm seeing throughout so much of the band.  But yes, our cameras did turn out to be at least a visible problem.

As for my noise level, that's been my life for the past 25 years now.  We have and now again do live in a subdivision with CC&R restrictions on antennas.  So I've been living with a B&W folded dipole (AKA my dummy load) in the attic.  My noise levels have been horrific!  I am looking forward to the delivery of a 24' flagpole antenna.  It has to be better in many ways.  I know that noise is worse in the vertical plane, but I'm convinced that ANYTHING would be better than my folded "dummy load".

Interestingly, even with the coax removed from my FLEX I still get a noise level of at least S3.

Thank you all, and your suggestion got me to try a couple of experiments I might have not done otherwise.  Cheers for now, and thanks again!

KD0RC

Excellent! Glad you found the source.  The noise level when connected to a dummy load or nothing at all will be profoundly influenced by your RF gain setting. Don't set RF gain trying to minimize the no signal S meter value.  You want about 8 - 10 dB noise floor difference between no antenna and your antenna for the band in question.  I got that from the documentation on this site somewhere and it has worked really well for me.

Len

K7JV

Thank you, Len.  Yes, hopefully we're gaining.  Sometimes I feel like the snail that climbs two feet up the inside wall of the well, and then wakes up the next morning to find that he's slid down three feet while he was asleep.

I saw that note about setting the RF Gain, too, and want to putz with that a bit. 

As for the noise thing, I'm a 40+ year ham with all of those tied up with rigs that only had AF Gain, RF Gain, IF Shift, NB and maybe a notch filter to work with.  These FLEX's are overflowing with settings and switches that can truly help.  I just need to learn how to use them.  I'm so hopeful that the new flagpole will bring some of the fun back.  My 25 years with a noise floor that pretty much kills 90% plus of the signals has left me just active on a couple of 75/80 meter nets and that's about it.  FARM meets nightly on 3937 and IMN nightly on 3572.  Both are traffic nets.  That's been my hamming for the past two and a half decades.  Fingers are crossed for the flagpole.

Thank you again, Len.  Cheers and best 73!

Mark_WS7M

Well if you do manage to get the flag pole up I'd recommend a Mag Loop receiving antenna.  So you use your flag pole to transmit, your mag loop to receive.

I'm probably going to do this myself.  I also live in CC&R neighborhood and while I've managed to slide by with wire loop antenna it does not tune well on many bands.

So I'm considering a BigIR vertical from SteppIR which I can conceal mostly behind a tree and hopefully paint it green.

For receive a mag look like those made by MFJ or Dx Engineering.

From everyone I've talked to you don't even need to get these up high.  Just away from metal and they are quiet and virtually invisible.

Steve Blankinship AG4SO

Have been following this with interest, I have the same spurs on several bands. Due to HOA restrictions my 6400 is remoted to a near by mountain top repeater site. The spurs started this winter, I have the Astron PS floating a battery with a Epic power gate. My antenna is a OFC up 40' off the tower. I have a remote coax switch that I use to isolate & ground the antenna as well as turn the radio and off  via a micro bit web switch. By grounding the antenna I have eliminated the radio source as being the radio. Looks like I will have to make a trip up this weekend to see if I can find the source. Jim glad you found it Thanks for the thoughts folks.   

Rocinante

Glad you found it. I have some fascinating repeating noise bands as well. After some basic experimentation, I discovered they were caused by the ceiling fans in my house which operate via a direct drive DC motor. They are dead quiet to the ear, but they generate some HF noise in the process of inverting from AC to DC and / or running the DC fan motor itself. If I turn off the ceiling fans, the noise disappears immediately.
On the topic of getting away with things in neighborhoods that disapprove of ham antennas, I am currently using an Ultimax 100 antenna with the 66' wire configuration. I string it between a couple of trees in my back yard, and the wire is so thin that nobody has noticed / complained about it yet. If they do I'll take it down and try something else, but so far that's working as well as one could expect with 100 watts and a wire strung up the side of the building, across to one tree, and then over to a second tree.

Doug

Removing the antenna on a Flex won't result in the meter reading 0, but what you are seeing. There has been page after page about this discussed here on the this forum. In addition unlike a R.F. gain on a **** radio the AGT won't affect the S-meter reading either like the R.F. gain setting

K7JV

Good morning all, and the saga continues.  I've done considerably more testing, and now feel that I have narrowed it down to three QRN/QRM issues to work on.

1)  Looking at the image I posted above, you should see it on a wider band display!  LOTS of spikes, all the way across!  Some are regularly spaced and some are random.  Well, it turns out that the evenly spaced spikes are from the Powerwerx switching power supply.  That is the power supply that FLEX routinely offers as a choice for these radios.  I did tune my receiver to several of the spikes attributable to the power supply, however, and there isn't much of an audio signal to really interfere with anything, so it may be more of a visual issue than an operating issue.  I am going to try putting RF chokes on the coax and on the power supply power AC and DC conductors to see if that makes any difference.

2)  The more random and taller spikes are widespread, as well.  And like Len said, security cameras are suspect.  It turns out that I can tag each individual spike, after having run my tests, to the camera that is generating the signal.  Those do have a nasty audio waveform associated with them.  I'm not sure what I can do about that, other than shutting down the cameras while I'm operating, and that's not a good solution.  I haven't tried the various filtering options on the FLEX to see if any of them individually or in combination can knock those signals down.  I am going to try putting RF chokes on the Ethernet cables from the cameras and see if that makes any difference.

3)  The S7+ noise floor just is a really big issue!!  I do have an antenna coming one of these days, and will see if I might not be able to do better.  I've had this noise level for 25 years now, ever since I migrated from some great outdoor antennas (Inverted "V" and a Cubex 4 element tri-band cubical quad) to nothing but the B&W folded dipole in the attic.  (CC&R's)  I really do hang a lot of blame on that, although I've not had any options to rule it in or rule it out. When I get my new Greyline 24' Flagpole antenna, we'll see how things compare.

That's about it for now.  My original testing missed my UPS loads and I hadn't tried taking the power supply out of the picture.  It is interesting to note that when I disconnect the antenna from the back of the FLEX, the noise floor drops to about S2.5 to S3 (RF Gain at mid-level or above) and EVERY ONE OF THE NOISE SPIKES are GONE!  So even the switching power supply spikes are coming in thru the antenna, not the radio's electronics.  Interesting.

Thank you all again for your terrific ideas and information.  As I said, the saga continues.  :-)  Cheers and best 73, and STAY WELL!!!

KD0RC

If the noise spikes are stable and stay at the same frequency, you can use the TNF function to notch them out.  If they are wandering around, the TNF is not so useful.  I have a few spurs here that I set up the TNF for.  Most are set to Normal, some Deep.  Once I have the sig notched out (I zoom all the way in to set it precisely and as narrow as possible) I click the Remember sub-function.  I just leave the TNF always active, and just forget about the interfering sigs. For tuner-uppers and other transient hetrodynes, I use TNF the same way, but don't hit the Remember function.  What you hit on is right - without a panadapter, we run across the same interference, but don't see it all at once, so it does not seem as bad.  With the Flex panadapter, we see more at once, and can more easily discern repeating patterns.

Do you use your WNB (Wideband Noise Blanker)?  In my case I get up to a 10 dB reduction in the noise floor depending on band and conditions.  I also leave this permanently enabled on all bands.  It can take a second or two (literally) to engage and knock the noise down so you have to engage it and wait to see if it has an effect.  I noticed the noise floor jumping up and down on 40 in a few second cycle.  Once I engage the WNB (set on 20 or so) the noise stops, and I see a steady noise floor.

73,
Len, KD0RC

K7JV

Great idea.  I'll experiment with the TNF.  I'm really looking forward to checking out what chokes might do.  I just need to get to the motorhome to retrieve them.  If I hang in there long enough, and with all of your help and the other help on the Community, I just may truly get the fun back into amateur radio.  :-)

Oh, I did turn on the WNB for the FARM net this evening, and my noise doesn't seem to be up its alley.  Dang.  Believe me, my noise floor is verrrrrry steady.

K7JV

Update - I put fairly large ferrite chokes on the 120 VAC supply cord to the Powerwerx power supply, on the 12 VDC output from there to the Powerwerx fuse block and on the 12 VDC line from the fuse block to the FLEX-6400.  I also put one of the large ferrite chokes on the Ethernet cable leaving the PoE switch to two of the RING cameras and one on the incoming Ethernet cable to the PoE switch that passes the cameras to the Internet.  I also put two of the large ferrite chokes on the antenna coax where it attaches to the radio.

Unfortunately I did NOT see any changes whatsoever on the FLEX padadapter's general noise level, the spikes that I've shown to be coming from the power supply or on a handful of spikes that I've identified as being generated by the two RING camera feeds.

At this point, I will wait for the new flagpole antenna and see what that does, and will try putting my old analog power supply from Kenwood on the radio and see what difference that makes.  The saga continues.

Mark_WS7M

I think think it would be worth your while to purchase like a $40 mag loop off eBay and just see if it helps with your noise level.  If so you could invest in a better one.

They are supposedly much quieter than verticals.

Roger Hartel

Similar issue in my shack and in remote ops.
After I eliminated all of the switchers, I shut the ethernet switches down and they were gone.
I applied many ferrite filters and reduced the levels, but they are still present.
Enjoy your TNF's.

NA0B

Very interesting thread! In my case, I had a major interference in 80 meters centered around 3550 Khz, about 30 Khz wide.  It turned out to be an old power **** with "filtering". I replaced it with a newer model and the interference is gone. So, check your (old) power strips for possible sources of interference.

Patrick

Stephen,  it could be and is most likely the inverters that can put radiated emissions out on the DC side (solar panel) and the AC side could be fairly clean, or not.  This is tricky because it means dealing with your neighbors.  You would have to put ferrite on the DC leads at the inverter within a quarter of a wave length of the top frequency you see.  The law (Federal) is on your side since the inverter should comply with Part 15 emissions rules.  Good luck.  

K7JV

Update - I believe that I have a pretty good handle on the noise and spurious signal issues at my now 6-week old FLEX-6400 / Maestro station.  I have three noise related issues:

1) I have periodic spurs of noise at regular intervals / Source is the Powerwerx switching power supply.  I put five RF chokes (the hinged magnetic chokes, about 1 3/8" OD, 1/2" ID and about 1 3/8" long) on the 12 V line that runs from the power supply to my RigRunner power ****, and the spikes were substantially reduced.  Yay!

2) I have numerous unevenly spaced, stronger and wider spurs of noise that are quite annoying when the receiver is tuned on top of one of them / Source is our RING cameras that are connected by Ethernet (PoE).  I tried putting up to six RF chokes on the Ethernet cable from the PoE switch coming from one of the offending cameras, and it made zero difference!  I truly believe that I need to research a different brand of security camera, or just live with these spikes.  Rats!!

3) I have a substantial noise floor, twenty-four-seven / I am hopeful that a new antenna that is "on the way" will be helpful.  Here's hoping!!!

There is a huge amount of relief in having identified what I think are all of the persistent noise and spurious sources of interference to my receiver.  Not knowing is very frustrating.  At least now I know what I'm dealing with.

Cheers all, and stay well!!