Help to identify this Noise

Sergey KN7K

Several times in a week I have the noise on 160m at level 59 and it make it impossible to use this band.
WNB, NB or NR do not help.
Does it look like the noise coming from AM stations? Or else?





Thanks
Sergey, KN7K

Stan VA7NF

Starting off this looks self-inflicted; your AM band has a sensitive antenna with a -40db signal strength, no 160M filter (in WIDE mode) and even +8db pre-amp engaged.
You have in-band mixing products (the peaks are all exactly 10Khz spacing) and I expect listening to the AM results you will hear AM stations at each peak, including the signals outside the BC band.
First likely-hood is mixing in the radio front-end - Turn off the preamp and see if the garbage drops more than the 8db preamp gain.
Second is mixing in a diode near, or in the antenna
I use a commercial BC band filter that knocks off 80db from .55 to 1.7Mhz inserted between AntA-in and AntA-out unless I'm SWLing for BC stations
Only after that start looking for other sources
p.s. There are likely other extra strong AM stations not showing on your panadapter below 1.360 contributing to the mixing source signals

Patrick

Most likely a switching power supply.  Notice the evenly spaced noise spikes.  They are usually related to the fundamental frequency of the power supply emitting the noise.  

Ha Gei

I am with PAT l this looks like a PSU or INVERTER or the like .. Is it thre ALL time or daytime related ?

Sergey KN7K

Well, I do not think it a PS - i do not use switching PS, it is Astron VS-35M.
It is appears on some days and not present on others, I did not make any notes yet, like day and time.
I can try another PS just to make sure...

Here is situation today at 12:30pm Pacific time by Band

Sergey KN7K

Few more 




And 0.4-14.500 MHZ, no preamp

Sergey, KN7K

David-N5PSM

what filter?  "I use a commercial BC band filter that knocks off 80db from .55 to 1.7Mhz"

Sergey KN7K

OK, it seems like not PS related.
I turned ON my Yaesu Ft5000MP and I see/hear the same noise on 160m - S9 level.
Seems like external.
Sergey, KN7K

Stan VA7NF

@David Had to dig it out of my rack.
Clifton Labs Z10020B NAVTEX version

Use it to **** BC band while SWL on aircraft beacons - Need gain on these VLF frequencies and cannot overload with BC signals.
@Sergey: 1) Your later images are a different time of day - Naturally because the original images are with 160M skip in (
Also all the latter images are with Flex filters in (not wide)
2) No question you have a mix of various noise sources
3) I see your 160M antenna also has peaks on 80 and 40M as the interference also has peaks on those bands.
4) Looking at your DC to14MHz view, you need BC band filtering when the skip is in

No time to investigate right now - Heading off to operate the VE7RAC sponsor station for the Canadian RAC Winter contest - Drop by and have a very brief talk to our YL SSB ops or this old, not so lovely, CW op.

Ken Wells

Two suggestions from my experience....

1) Do you have a lightning protector inline with the antenna?
It is possible that it has been hit but did not fail completely.  Sometimes they become semi-conductor and mix broadcast AM and can generate lots of junk.

Temporarily take it out of the line and test to see if anything changes.
If so, replace it with a new one, or replace the protection element.
If not, put it back in line....

2) This also looks similar to the trash generated by one of the "Hockey puck" style of halogen under counter lights in my kitchen.  Either a bad, arcing light bulb, or a bad, arcing wall plug power transformer generated this mess.  When I unplugged the transformer and quit using the lights, the problem went away.

Sergey KN7K

I do not see Clifton Labs Z10020B NAVTEX version is available anywhere.
Cliffon Labs was purchased by DX Engineering.

DX Engineering offer this model for BroadBand
https://www.dxengineering.com/parts/dlw-fl1718

Sergey, KN7K

Robert Lonn

Looks a lot like a Malfunctioning SOLAR Power Array!!!! 

Sergey KN7K

Ken,
I pretty much removed everything from the line - no lightning protector now.
Cable from the radio goes through line isolator and 43ft transformer at the base.

All house is "dark" - no lights, just Fridge and my radio.
Well, few wallwarts that always on, so i am not suspect them (yet).
Either Flex or FT5000 see the same noise, so since FT5000 uses internal PS, I do not suspect my Astron VS35M.

I see that pretty often, it comes and goes.
That's why I am not sure if it a boadcast or not, other wise I would see it all the time.

I suspect my neighbors may have some devices that make this noise to appear, but I cannot go around and ask.

The question is what kind of filtering may help here, or how can I isolate it -  is related to broadcast below 1.7mhz or not?

Sergey, KN7K
 

Ha Gei

This is why i asked..  maybe a solar panel OPTIMIZER , they can easily interfere over 100 meters away.

Sergey KN7K

I do not see all houses around if the have a solar panels or not, could be other side that I do not see.
typically I see it once or twice every week, but last 2 days this noise is there all the time.
i guess I have to wait a little longer to find out if it coming from Christmas lights on the street.
i will borrow a BPF from a friend to try if it helps.
thanks
sergey, KN7K 

Patrick

There are lots of switching PS’s out there.  I fixed most all of mine...  on going!  But I Have two outside sources, one a city LED street light with out of spec RFI issues, which I am trying to get them to fix.   The other more difficult an appliance like a computer with a bad PS, or some other device that is only used during the day, disappears at night.  So RFI is a constant issue and a never ending battle.  

Patrick

BPF’s will not help as you will still see the noise spikes in band.  It will reduce them outside of the filter BP but that part does not matter to the signal within the BP.   Source elimination is the answer...  by fixing the device it’s self or at least filtering at the source with ferrite. 

Sergey KN7K

Thank you Pat.
i understand that RFI is a battle, especially when I live on a small city lot with many houses on the front of my house and apartment complex on the back.
i still wonder if I should get a broadband filter to eliminate possible noise from AM stations. I see the closest one from Portland to Vancouver is about 6 miles away and very very loud on 1520khz.
i guess there is no way to verify if it’s coming from AM band without purchasing such filter.
sergey, Kn7K 

Patrick

I live less then six miles from most of the AM broadcast stations here on Kauai.  I have a very good filter, but it has practically no observable affects on the overall band pass of the ADC output.  This is a tribute to the Flex 6000’s immunity to overload.  

Uwe - DK3WW

Hello,
I had the same characteristic noise here. This came from a battery charger for acid batteries. It was about 400m from my home. I bought a new charger for this neighbor (no switching charger). Finding the source of the interference is the most difficult thing of all... Good luck searching!
73! Uwe
DK3WW

Ha Gei

I lately heard in a talk with the DARC EMV Speciailists, that the increasing use of Electric cars , bikes and especially these cheap chinese hoverboards etc. etc.  will create big problems in the future for interference possibilities. So keep eyes open when you see something swirling around  the neighborhood with no "twin" sound.

Sergey KN7K

Thanks everyone for reply’s,
I am pretty sure I isolated 99% everything in my house and from here I only can try to block AM stations, even I am not sure it will help. I ordered broadband filter for below 1.7mhz.
if this filter will not help, I do not have many options as I live in HOA and have CCR’s and both my antennas hidden between trees - 2el Steppir and 43ft vertical, so I am not in the position to knock to the neighbors doors with questions. Also, right behind my backyard, I have an Apartments, that make it impossible to find out the source.

Noise was very bad through last week of December, almost no noise on Jan 1-Jan4, came back yesterday around 3pm when I was finishing my ARRL RTTY RU contest, blocked pretty much all bands.
Sergey, KN7K 

Robert Lonn

You may need to do some DF ( Direction Finding). If you have any type of portable SWL radio with an external antenna input, you could go looking for it with a DF antenna.. I once used my Grundig  Satellit 750 radio with it switched to the external Antenna position. Almost any BEAM type antenna will work. I used one that was for the UHF band on 14 MHz, and it worked OK. Since we are not transmitting SWR is a mood point.. I was SHOCKED to find the interference was almost 2 blocks away, and it turned out to be a Solar Panel System.

The owners were interested in all of this! I told them about it being intermittent, and appeared something might be malfunctioning?? I gave them my number to call me if they find something out! About a week later, I had noticed the interference seemed to have stopped?? I got a call from them stating that the entire solar system had "Lost Its Ground"!! They said it was also affecting how the Reverse Power Meter was  "Turning the meter backwards" and affected their credit for the system! They think I may have saved them a lot of money as they did notice an increase in their electric bill, and they did not know why??

All this from a faulty ground connection.. Many of us have seem a LOT of RF interference issues over the years.. When transmitting thousands of watts,, the older Analog TV sets would go crazy!! It was a lot of work to clean up RFI in TV sets!!  

Robert

Patrick

Just a comment about Electric cars.  Having worked in this area and also the owner of an electric car.  It is much less likely that electric cars will be a source of interference.  They are more thoroughly tested then most other devices and must withstand interference (very well shielded and filtered) for safety reasons.  The chargers are all actually built into the car.  The so called charging device is just an interface that contains the items needed to protect the user and the car from external sourced problems.  

Sergey KN7K

Thank you Robert,
Unfortunately I do not have handheld receiver besides 144/430mhz, so it will be hard to find it for HF. I will ask around if someone have a mobile station.

By the way, yesterday all bands from 160m to 20m were blocked with spikes, but today is really quiet



Sergey, KN7K

Ha Gei

Not even a simple shortwave radio ?  maybe some SDR Stick  ?
as long as you can´t find the source..you will suffer.. 

Sergey KN7K

Actually I do have SDR play Duo and I may connect it to laptop and drive around.
Thanks for a great idea.
Sergey, KN7K

Robert Lonn

That will work! Nothing like a high quality spectrum analyzer, but those are expensive and most folks dont need such items. DF can be a FUN part of Ham Radio.. Was part of those many moons ago!! DF goes Way Back!!

Sergey KN7K

Sure, it would be fun to drive in my neighborhood on such track

Sergey, KN7K