wb6uqa
Member
Turn off electricity to your house. Listen on battery receiver. Make sure noise is coming from your house. Buy a radio like a IC 7300 with good noise blanker.If noise comes from your house turn circuits off one at a time.
Reducing noise floor, fixable or just luck, Help/Advice
- Thread starter osros
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wb6uqa
Member
Call your power company. Most have a noise guy. Make a small directional antenna and locate the noise yourself. Mfj sells a noise finder with a directional antenna under 200.
wb6uqa
Member
Try the Timewave Anc4 or MFJ 1026 noise eliminators .A lot of solar storms now.See if other people in your area hear the same noise.Call the arrl play it for them and they will tell you what it is.
jim202
Member
I might have missed it in reading the entire thread here, but have you tried to kill the entire house electrical feed at the main disconnect or main breaker? This will remove the house from the equation on looking for the source of your noise.
Noise floor searching can take months or longer to locate the source of it. Once you have determined if it is inside your house or external, you know which way to go. The use of a battery operated receiver is your best friend in this case. Sometimes using the AM portion of your auto radio tuned to a channel with no station can be used. Just drive around and try to find an area with the worst noise. Trying to track it down even further can be a very time consuming problem.
If it is in the house, that makes it much more controllable. But locating the source or sources will test your temper and skills. I have found that in my workshop where my radios are, there were 2 different florescent light fixtures that were giving me problems. One was solved by removing the pair of 4 foot tubes. The other I think has a bad ballast and it took disconnecting the power to it to kill the noise. One of these days, I will pick up some new complete fixtures and replace both of them and have my lighting back.
Other noise could come from a simple item like the transformer that feeds the front door bell or chime. The problem is trying to locate where they hid the transformer.
Another source could be from the heater in a fish tank. But you would notice it going on and off.
The more likely source is a cracked insulator or loose connection out on the street utility poles. The best way to locate these and the buzz they make on the radio is to drive around with your vehicle and try to locate the peak in the noise. Make a good note where it is. Then come back when it's dark outside with a big sledge hammer and wack the pole about 4 or 5 feet up from the ground.
What your trying to do is shake the pole and see if the noise changes. You might cause some interest in the neighborhood with the loud crack noise form hitting the pole. That's why I say do it when it's dark out so your actions can blend into the darkness. This type of noise will change with the weather. it might get worse with dry or wet weather. So try to make a note if it changes with dampness.
On the electrical meter ground rod, if the clamp has rotted off, you probably should just replace the ground rod itself also. The ground rods don't last forever and loose their low resistance with time. They corrode and cause the ground connection to become very poor. The rate at which this happens is dependent on the soil conditions. Just go get another one from Lowe's or home Depot. Depending on your soil conditions, the longer the better. They come in both 8 foot and 10 foot lengths. If you have sandy soil, it might take connecting several rods together to get a low resistance ground.
They make rods with the ends that are threaded. Then you use a threaded coupler to just screw them together. Make sure to use some anti oxide compound on the threads if you need to go this route. There is also a driving attachment to use so you don't destroy the top end of the rod while trying to drive it into the ground.
Good luck on trying to locate your noise. Let the rest of us on here know how you make out in solving the noise problem. We all learn from what others have done.
Noise floor searching can take months or longer to locate the source of it. Once you have determined if it is inside your house or external, you know which way to go. The use of a battery operated receiver is your best friend in this case. Sometimes using the AM portion of your auto radio tuned to a channel with no station can be used. Just drive around and try to find an area with the worst noise. Trying to track it down even further can be a very time consuming problem.
If it is in the house, that makes it much more controllable. But locating the source or sources will test your temper and skills. I have found that in my workshop where my radios are, there were 2 different florescent light fixtures that were giving me problems. One was solved by removing the pair of 4 foot tubes. The other I think has a bad ballast and it took disconnecting the power to it to kill the noise. One of these days, I will pick up some new complete fixtures and replace both of them and have my lighting back.
Other noise could come from a simple item like the transformer that feeds the front door bell or chime. The problem is trying to locate where they hid the transformer.
Another source could be from the heater in a fish tank. But you would notice it going on and off.
The more likely source is a cracked insulator or loose connection out on the street utility poles. The best way to locate these and the buzz they make on the radio is to drive around with your vehicle and try to locate the peak in the noise. Make a good note where it is. Then come back when it's dark outside with a big sledge hammer and wack the pole about 4 or 5 feet up from the ground.
What your trying to do is shake the pole and see if the noise changes. You might cause some interest in the neighborhood with the loud crack noise form hitting the pole. That's why I say do it when it's dark out so your actions can blend into the darkness. This type of noise will change with the weather. it might get worse with dry or wet weather. So try to make a note if it changes with dampness.
On the electrical meter ground rod, if the clamp has rotted off, you probably should just replace the ground rod itself also. The ground rods don't last forever and loose their low resistance with time. They corrode and cause the ground connection to become very poor. The rate at which this happens is dependent on the soil conditions. Just go get another one from Lowe's or home Depot. Depending on your soil conditions, the longer the better. They come in both 8 foot and 10 foot lengths. If you have sandy soil, it might take connecting several rods together to get a low resistance ground.
They make rods with the ends that are threaded. Then you use a threaded coupler to just screw them together. Make sure to use some anti oxide compound on the threads if you need to go this route. There is also a driving attachment to use so you don't destroy the top end of the rod while trying to drive it into the ground.
Good luck on trying to locate your noise. Let the rest of us on here know how you make out in solving the noise problem. We all learn from what others have done.
osros
Member
Thanks all,
Alot to do, I realized my SDR and PC setup I can run on battery, SDR is USB only and the PC is a Tablet/Laptop so I can get it away from the house or cut of power pretty much right away. I will need to conduct the test next time I have the place to myself, which should not be long. I will go from there.
I not sure I will be able to pull off the hammer and pole thing without getting arrested or them at least showing up something I rather not deal with yet since my wife part of the law. But dont mind driving around trying to find the source but lets get there first. I will post my progress.
I was getting discouraged but Im not going to let it spoil my fun. I will get my lic and get on the air anyway there seems to be alot of fun things to do and try, I will go mobile if I have to always wanted to setup a car basecamp and DX and try higher elevations. I also want to try QRP different locations see what I can do.
Alot to do, I realized my SDR and PC setup I can run on battery, SDR is USB only and the PC is a Tablet/Laptop so I can get it away from the house or cut of power pretty much right away. I will need to conduct the test next time I have the place to myself, which should not be long. I will go from there.
I not sure I will be able to pull off the hammer and pole thing without getting arrested or them at least showing up something I rather not deal with yet since my wife part of the law. But dont mind driving around trying to find the source but lets get there first. I will post my progress.
I was getting discouraged but Im not going to let it spoil my fun. I will get my lic and get on the air anyway there seems to be alot of fun things to do and try, I will go mobile if I have to always wanted to setup a car basecamp and DX and try higher elevations. I also want to try QRP different locations see what I can do.
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majoco
Stirrer
I feel that your interference must be very local, very likely in your house, something that you would least suspect.
I have attached a pic of my SDR tuned to Radio China on 9675kHz at 0130UTC/1330local.
You can see that although the noise level seems excessively low at -130dBm and the signal peaking at around -90dB, the signal to noise radio is still a very good 40dB. In the house at the moment the only things on are a few CFL lamps including one right over the radio, a couple of fridge/freezers and most of the radios in the shack. CFL lamps here run on 240volts so I don't think they make anywhere near as much noise as you 120volt versions. I know that if I turn on the heat pump, the dishwasher and the washing machine I will bring up the noise by 10 to 20dB! After 3pm when the kids come home from school, the neighbour's TV brings in a lot of video hash so I think they must have a plasma!
So the advice you have been given to cruise around your house with a portable and even outside, turn everything off except for the SDR, try another computer etc are all valid responses - so just keep trying. You may even load the SDR and laptop into you car if they run on 12volts and drive around the neighbourhood - you may find that dodgy pole transformer or cracked insulator - does the noise increase with damp conditions - that's would be a clue. You'll be very happy when you find it.
I have attached a pic of my SDR tuned to Radio China on 9675kHz at 0130UTC/1330local.
You can see that although the noise level seems excessively low at -130dBm and the signal peaking at around -90dB, the signal to noise radio is still a very good 40dB. In the house at the moment the only things on are a few CFL lamps including one right over the radio, a couple of fridge/freezers and most of the radios in the shack. CFL lamps here run on 240volts so I don't think they make anywhere near as much noise as you 120volt versions. I know that if I turn on the heat pump, the dishwasher and the washing machine I will bring up the noise by 10 to 20dB! After 3pm when the kids come home from school, the neighbour's TV brings in a lot of video hash so I think they must have a plasma!
So the advice you have been given to cruise around your house with a portable and even outside, turn everything off except for the SDR, try another computer etc are all valid responses - so just keep trying. You may even load the SDR and laptop into you car if they run on 12volts and drive around the neighbourhood - you may find that dodgy pole transformer or cracked insulator - does the noise increase with damp conditions - that's would be a clue. You'll be very happy when you find it.
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osros
Member
Thanks majaco, Im jealous 
Well did a quick house power cut off test and as if things could not get worse. I guess good news and bad news. I got two videos for before and after to sum up, power cut off noise floor improves gets down to -110 to -120 across HF but it also brought out all the external noise thats was buried before. I can now see and hear the external RFI a lot better so my problem is two fold. Its getting like I dont know if I can even fix this.
House power ON: https://youtu.be/DbbU-AYyDQE
House power OFF: https://youtu.be/8djMTSlktVQ
Well did a quick house power cut off test and as if things could not get worse. I guess good news and bad news. I got two videos for before and after to sum up, power cut off noise floor improves gets down to -110 to -120 across HF but it also brought out all the external noise thats was buried before. I can now see and hear the external RFI a lot better so my problem is two fold. Its getting like I dont know if I can even fix this.
House power ON: https://youtu.be/DbbU-AYyDQE
House power OFF: https://youtu.be/8djMTSlktVQ
majoco
Stirrer
You said you had a wire about 10ft high and 45ft long - but how do you get the signal into your house? I have two Off-centre fed dipoles (OCFD) almost in parallel above my roof but the feed point has a 9:1 RF transformer then coax down to the receivers almost underneath - this is an old pic that only has one OCFD. The transformer has the effect of cancelling out any local low frequency interference picked up by both legs but not cancelling the HF signals - and also matches the high impedance of the antenna to the low impedance of the cable and the radio/multicoupler.
I think you might find as you go around your house there will be some motor or switch mode power supply that is making most of the noise - try switching them back on one at at time.
I wouldn't worry too much about an earth system not complying with the NEC requirements and voiding your house insurance in case of a claim - if your antenna is struck by lightning most of the evidence will be vapourised!
I think you might find as you go around your house there will be some motor or switch mode power supply that is making most of the noise - try switching them back on one at at time.
I wouldn't worry too much about an earth system not complying with the NEC requirements and voiding your house insurance in case of a claim - if your antenna is struck by lightning most of the evidence will be vapourised!
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osros
Member
Thanks,
Basically I have a feed end of the Ant outside above the shack at the window 8-10ft high and run straight out Horiz to a tree almost parallel to the house but more of a NE direction moving away from the house, however I realized moving closer to the electrical pole. no ground atm. It is a simple throw up thing for SWL only.
Now that Im getting more serious and trying to learn all this Ant stuff I want to do better and reduce some of the noise floor. I am in the process of selecting and ordering items for a proper RX/TX antenna setup for HF. Before I get too crazy I think I need to setup a proper Ant and fix some basic issues before I start beating electrical poles with sledge hammers.
My house limitations are I have trees on me and all around me blocking mast and ant antenna options, then power lines reducing it more, driveways, then finally if I get away from all that which is possible I have a coax run that will be extreme which Im still trying so see if there is anything I can do there. Also thinking how I can make these trees work for me instead of being a pain. I got a few ideas but dont know if any good.
NEC not really a concern it will be followed for the house portion. The antenna I am 90% sure will be a temporary mast with wire setup away from the house approx 25ft or more walk up when I use, walk down when not just need to figure out the easiest way. I may ground it not sure just going to treat it as a portable setup until I see whats works best, where and final antenna used then I will think of a more permanent deal.
Yeah now that I know 50% of my problem is in house will start to track it down.
wb6uqa
Member
The reason for turning off each breaker on at a time is to find what part of your house the noise is coming from.Removing each layer of noise is a victory.
Kb2Jpd
Member
Tunable Magnetic loop antennas are available at low cost for AM use. With a little soldering, you can make it tunable to the SWbands.
Sent from my iPhone using Tapatalk
Been kinda following this thread the past few days and several things come to mind.
First, by all means make sure that your house electrical service and associated wiring is safe especially with regard to grounding and bonding. However, don't be too disappointed if this does little or nothing to cure your radio noise problem.
The noise is coming from one or more sources either something on the power line in your house, or over the power line from a neighboring house, or radiated through the air from a nearby source indoors or outdoors. Unfortunately you have little or no control over the sources outside your home.
The good news is that there are ways to reduce the affect of the noise. Sounds like at present you have a very simple wire swl antenna. If you have just a wire lead-in (no coax), the lead-in will pick up power line noise as it gets near the house no matter how far away you have the antenna. You need a shielded lead-in. Running the antenna in a different direction (if possible) may help reducing the noise... experimentation is required. You may want to check out the MFJ 1026 noise cancelling device. Got one recently for the shack here and it really does a good job in cutting down on the power line noise. Others have had luck with loop antennas, do a search, tons of info out there on building one of these. Good luck, keep us posted on your progress.
First, by all means make sure that your house electrical service and associated wiring is safe especially with regard to grounding and bonding. However, don't be too disappointed if this does little or nothing to cure your radio noise problem.
The noise is coming from one or more sources either something on the power line in your house, or over the power line from a neighboring house, or radiated through the air from a nearby source indoors or outdoors. Unfortunately you have little or no control over the sources outside your home.
The good news is that there are ways to reduce the affect of the noise. Sounds like at present you have a very simple wire swl antenna. If you have just a wire lead-in (no coax), the lead-in will pick up power line noise as it gets near the house no matter how far away you have the antenna. You need a shielded lead-in. Running the antenna in a different direction (if possible) may help reducing the noise... experimentation is required. You may want to check out the MFJ 1026 noise cancelling device. Got one recently for the shack here and it really does a good job in cutting down on the power line noise. Others have had luck with loop antennas, do a search, tons of info out there on building one of these. Good luck, keep us posted on your progress.
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osros
Member
Thanks,
Yes definitely looking at correcting my issues, I do have coax to the antenna but the antenna itself is not grounded. I am happy to report I just go in my portable mast from GoVertical and I like what I see so far. It will be fun to try out different antenna configurations and this mast will make it possible to try out different things without me killing myself.
Getting a good antenna property setup Im sure will help or at least take one thing out of the equation so looking forward to getting the rest of my stuff ordered, Antenna is next and guy accessories. Like I said Im looking at a wire antenna as a portable or temp setup, up when I need it, down if not in use for a while. I am also getting it away from the house a bit hopefully it will help some.
Will be a a couple of weeks or so but will post pics when I erect it.
Yes definitely looking at correcting my issues, I do have coax to the antenna but the antenna itself is not grounded. I am happy to report I just go in my portable mast from GoVertical and I like what I see so far. It will be fun to try out different antenna configurations and this mast will make it possible to try out different things without me killing myself.
Getting a good antenna property setup Im sure will help or at least take one thing out of the equation so looking forward to getting the rest of my stuff ordered, Antenna is next and guy accessories. Like I said Im looking at a wire antenna as a portable or temp setup, up when I need it, down if not in use for a while. I am also getting it away from the house a bit hopefully it will help some.
Will be a a couple of weeks or so but will post pics when I erect it.
osros
Member
Initial findings for cutting power, I found one circuit breaker that has a significant effect on the noise floor from -80db to about -100db when off. The good news is thats the only one I can see changing things the bad news it is tied in to about 3 rooms of the house. I unplugged everything in those rooms the noise returns when I switch back on the breaker without anything plugged in.
Either its something I dont see/hidden or its just the funky wiring in the house which I dont see if I can even fix that.
Either its something I dont see/hidden or its just the funky wiring in the house which I dont see if I can even fix that.
Frustrating isn't it. Tracking this stuff down can be tedious.
Anyway, several things: perhaps as you suggested you missed something that is still on the circuit after you thought every thing was unplugged. Go around the house with a portable AM radio tuned to a frequency between stations so that you hear just the noise. Use the portable radio as a direction finder and hopefully locate the noise source. Also, as you mentioned, funky wiring may be the culprit. There may be a loose bad connection somewhere on the circuit that is arcing. Again, the portable radio will track this down. Another thing to consider is this; maybe you did unplug everything and maybe the wiring is OK but that circuit is acting as a giant receive antenna for noise from outside the home. When you switch it back on, it couples the noise into the rest of your house wiring.
Switching various house circuits in and out can produce results that will have you scratching your head. Typical house wiring is unshielded and it can easily pick up and re-radiate noise.
Meanwhile, do some more detective work with the portable radio and see what you can find.
Anyway, several things: perhaps as you suggested you missed something that is still on the circuit after you thought every thing was unplugged. Go around the house with a portable AM radio tuned to a frequency between stations so that you hear just the noise. Use the portable radio as a direction finder and hopefully locate the noise source. Also, as you mentioned, funky wiring may be the culprit. There may be a loose bad connection somewhere on the circuit that is arcing. Again, the portable radio will track this down. Another thing to consider is this; maybe you did unplug everything and maybe the wiring is OK but that circuit is acting as a giant receive antenna for noise from outside the home. When you switch it back on, it couples the noise into the rest of your house wiring.
Switching various house circuits in and out can produce results that will have you scratching your head. Typical house wiring is unshielded and it can easily pick up and re-radiate noise.
Meanwhile, do some more detective work with the portable radio and see what you can find.
wb6uqa
Member
It has to be something. Faulty wiring will cause a fire. Find it fix it. Use a portable receiver to find it.
prcguy
Member
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I agree with the last part that switching in a circuit can route noise to that area. Is the area most affected by switching the breaker back on near the antenna by chance?
prcguy
prcguy
Kb2Jpd
Member
Replace the circuit breaker first. It's is functional but generating the hash.
Sent from my iPhone using Tapatalk
osros
Member
Well its not right near but its not a very big house either so not that far also, tough one to judge. Im in process of changing the Antenna system so I kinda holding on noise fixes besides grounding for now until Im happy with new antenna up and working I will then look again to see if my noise has improved or got worse and go from there.
I got a big update for you guys in post here in a bit.
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osros
Member
Shack Updates
An expensive weekend and some Ant progress made. I picked my Icom IC7300 my new center piece radio and my first base transceiver. I also got the Alinco 30A Power supply since they boast its a communications rated power supply for low or no RFI.
I put up my 30ft portable mast. It took longer than I thought since I really set it up as a semi-permanent install. I still have some guy rope adjustments to do but this was just a trial run no Antenna on it yet so will finalize it when I have the antenna on. The base of the mast is a but rough I know some rigging, the tie raps are no longer needed, but its so I can walk it up and down with one person. I plan on a downward slope for the end fed antenna. Using trees and fence post for some support. The location is best I can come up with trying to keep alittle away from the house and power lines. One stupid thing is I did not measure for my coax run yet I just hope its not over 100ft. I think I will be okay, but the shack is on the other side of the house.
An expensive weekend and some Ant progress made. I picked my Icom IC7300 my new center piece radio and my first base transceiver. I also got the Alinco 30A Power supply since they boast its a communications rated power supply for low or no RFI.
I put up my 30ft portable mast. It took longer than I thought since I really set it up as a semi-permanent install. I still have some guy rope adjustments to do but this was just a trial run no Antenna on it yet so will finalize it when I have the antenna on. The base of the mast is a but rough I know some rigging, the tie raps are no longer needed, but its so I can walk it up and down with one person. I plan on a downward slope for the end fed antenna. Using trees and fence post for some support. The location is best I can come up with trying to keep alittle away from the house and power lines. One stupid thing is I did not measure for my coax run yet I just hope its not over 100ft. I think I will be okay, but the shack is on the other side of the house.
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