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[Articles Home]  [Add Article]  

The Noise Is Deafening

Dick Boley (N3HKN) on May 8, 2017
View comments about this article!

Living in a condominium complex presents the usual antenna difficulties. These can be dealt with using a bit of imagination. However, the noise is another matter. Here it is always S-7, sometimes going to S-9. There is no particular characteristic such as pulses, tones, etc. -- Just a general high noise level. Not the type of noise that can easily be "phased out" with noise cancellers.

To further complicate the issue I must limit my power levels due to the proximity of the antenna - End-fed hanging from a second story window.

So, I feel that the hobby, after many years, has become a dead end. Maybe the pending legislation will happen but until then I am QRT.

Member Comments:
This article has expired. No more comments may be added.
 
The Noise Is Deafening  
by AK4YH on May 8, 2017 Mail this to a friend!
Shouldn't this have been a forum post, not an "article?"

Gil.
 
The Noise Is Deafening  
by KK7JS on May 8, 2017 Mail this to a friend!
Your experience sounds very similar to my recent problem with RFI. I found out that I had a nearby utility power pole that was arcing; it put out constant s7-s9+ noise. If you have any utility poles nearby try to drive/walk near them with an AM radio tuned to a empty or weak station frequency. If you get a strong noise/static reaction from one of them then you have your culprit. I called up my local utility to inform them of the problem - they should be grateful to hear about it as the power used to create that RFI represents lost $$$ for them. I asked specifically to speak with an engineer or a lineman to make sure the problem was understood and to give them any technical details they wanted.

Of course, your problem could be something else entirely. The ARRL does have a book about sources of RFI and how to deal with them. You might check it out to see if it can be of some help.
 
The Noise Is Deafening  
by W3DBB on May 8, 2017 Mail this to a friend!
When I go to the ocean or stay overnight in a hotel the noise from CFLs, Wi-Fi, various switching power supplies, and God knows what else makes listening darn near impossible. You have to hear them before you can work them. Noise levels are as described by the original poster. The FCC, in its role as industry cheerleader and quasi-, occasional, and selective regulator decidedly dropped the ball on this one.

Wide swaths of the US are plagued with high levels of radiated and conducted noise. Battery operation helps, true balanced antennas & true balanced tuners help, but the noise is overwhelming in areas with high density housing, again, as described by the original poster.

The large domestic broadcasting cartels don't seem to care. AM broadcasters probably figure RFI doesn't preclude listening to the local AM station while having the advantage of covering potential out-of-local service area competition for listenership. What is probably the main reason for their silence is it's the FM that still makes broadcasters some money.

I seem to recall the new FCC chief, in his earlier role as a Commission member, made some noise (no pun intended) about RFI and IBOC HD Radio making the kind of skywave AM broadcasting he grew up listening to unavailable to much of the current population.
 
The Noise Is Deafening  
by K0UA on May 8, 2017 Mail this to a friend!
Maybe try Echolink? Or 2 Meter or 440 FM? Living in a condo, I would not expect to operate HF. You have people living right in your hip pocket and you cannot control which RFI generating products they will buy and deploy literally the width of a sheetrock wall from your living space. It is bad enough for me to track down and eliminate all the RFI generating power supplys/products in my own house.
 
The Noise Is Deafening  
by KC4ZGP on May 8, 2017 Mail this to a friend!

Move.

73 and wear that seat belt.

Kraus
 
RE: The Noise Is Deafening  
by LZ1ABC on May 8, 2017 Mail this to a friend!
I am using an active antenna for receiving only. It as a small loop (1m in diameter) plus amplifier. Without it I am unable to work in the night as the QRN is S7 and above. There are many producers, I am using the one my father has build (lz1aq).

73 de Chav/lz1abc
 
RE: The Noise Is Deafening  
by N4CQR on May 8, 2017 Mail this to a friend!
When you figure in, HD TVs, Computers, Routers, and, Damn near every thing being wireless it was bound to happen. My NEST equipment as well as the burglar alarm and outdoor cameras makes HF operation from my home impossible.

Back in the day, I did not need so much electronics however in that day and time there far fewer crooks and dope heads.

73 Craig
 
The Noise Is Deafening  
by AC2RY on May 8, 2017 Mail this to a friend!
There is no real solution to that. I have found the same thing when I was building my first HF antenna. When I moved it 50 feet away from house, noise got down significantly. Finally now antenna is 100 feet away from house structure and noise level is acceptable for work with DX.
 
The Noise Is Deafening  
by K8PC on May 8, 2017 Mail this to a friend!
My noise level is anywhere from S9 to S9+20. I recently bought an MFJ 1026 noise cancelling device and it has literally given me back the hobby. If you purchase from MFJ and it doesn't do the job you have 30 days to return it. You do need a separate receive only antenna. In my situation I can now enjoy the hobby with an S4-5 on 40M and an S2-3 on 20M.

Pat
 
RE: The Noise Is Deafening  
by N3HKN on May 8, 2017 Mail this to a friend!
I bought the MFJ unit and with a lot of tuning, plus receive antenna fiddling, I had spots where noise was down to 3db. But slight antenna movement, or possibly activity in adjacent household, made that short lived. I returned the device.
 
The Noise Is Deafening  
by KC2WI on May 8, 2017 Mail this to a friend!
RFI is getting worse and not just on HF.

Back when the general public listened to real radio (particularly AM) they know and cared about RFI even if they didn't really understand it. But now, the vast majority listen to downloaded mp3s or Internet "radio" on their smart phones, have cable or satellite TV, and other such services. RFI is not a problem for them, therefore they don't know or care about it. Therefore it's not a problem they are complaining about and it isn't going to get fixed.

I don't see any solution and I think things are going to get worse between the increase in RFI and poor propagation due to minimal sunspot activity.

I have an ANC-4 for HF. It works some of the time. The trick is to locate the noise antenna where it picks up as much locally-generated noose as possible and as little of the desired signal. You shut the unit off, note the average noise level, then disconnect the main antenna and adjust the unit's gain to match that level. Then reconnect the main antenna and adjust the phase and fine-tune the gain to null out noise.

The other 'solution' is to use a DV mode like DSTAR, DMR, or Fusion with a local hot spot you build or a computer-only device like a ThumbDV. You connect to a reflector or talk group and can communicate with other hams far away. Trouble is, the long distance connection is not real radio, it's the Internet.
 
RE: The Noise Is Deafening  
by N3HEE on May 8, 2017 Mail this to a friend!
Dick. Perhaps try operating a remote station using RemoteHams.Com software. There are many HF remote stations available to use. It's all free! Joe N3HEE
 
RE: The Noise Is Deafening  
by K6CRC on May 8, 2017 Mail this to a friend!
I agree with previous posts. If the noise is generated by wall warts, plasma TVs, or Grow lamps, not much you can do. But, if it is from power poles, there are ways to mitigate it.
i took a portable AM radio and walked the neighborhood. Could ID several power poles that were very noisy.
Local Utility came out, cleaned a few and replaced a top bar/insulator on one. They are willing to do it, as the noise indicates a problem.
 
RE: The Noise Is Deafening  
by N3HEE on May 8, 2017 Mail this to a friend!
RFI is just a way of life today. It's not going to get any better. We must find ways to deal with it. The best way to reduce noise is to use a seperate receive antenna. This could be a simple piece of wire laying on the ground. Try an E-Field antenna. They are very small and simple to make and are designed to reduce man made noise. Dont give up ! -Joe N3HEE
 
The Noise Is Deafening  
by K0RGR on May 8, 2017 Mail this to a friend!
We used to know how to make a really effective noise blanker, and we could really use them today. The Collins S Line receivers had an optional blanker that was fantastic, and the one in the Drake TR-4 was equally impressive. They both featured separate 'noise receiver' circuitry - an actual 40 MHz receiver in the Collins case - that was used to blank out the noise in the radio's IF. A friend of mine had the worst noisy power line I've ever seen - noise often far above S9 - and the Collins blanker totally eliminated it.

The other makers, particularly the Japanese, started calling their diode noise clippers 'blankers'. These are not nearly as effective. Over time, the blankers have improved, but I really haven't seen one like the old Collins, though I have heard good things about the optional blanker in later Ten Tec radios.

I would suggest that you look into remote operations. I suspect that I will probably be a condo dweller eventually, and beyond VHF and UHF, I think that's the route I'm going to take. That and mobile/portable operations. There are both 'free' and 'fee' remote setups available, and the price of using the 'fee' ones seems to bave improved lately.
 
The Noise Is Deafening  
by K0RGR on May 8, 2017 Mail this to a friend!
We used to know how to make a really effective noise blanker, and we could really use them today. The Collins S Line receivers had an optional blanker that was fantastic, and the one in the Drake TR-4 was equally impressive. They both featured separate 'noise receiver' circuitry - an actual 40 MHz receiver in the Collins case - that was used to blank out the noise in the radio's IF. A friend of mine had the worst noisy power line I've ever seen - noise often far above S9 - and the Collins blanker totally eliminated it.

The other makers, particularly the Japanese, started calling their diode noise clippers 'blankers'. These are not nearly as effective. Over time, the blankers have improved, but I really haven't seen one like the old Collins, though I have heard good things about the optional blanker in later Ten Tec radios.

I would suggest that you look into remote operations. I suspect that I will probably be a condo dweller eventually, and beyond VHF and UHF, I think that's the route I'm going to take. That and mobile/portable operations. There are both 'free' and 'fee' remote setups available, and the price of using the 'fee' ones seems to bave improved lately.
 
The Noise Is Deafening  
by W3TTT on May 8, 2017 Mail this to a friend!
I was considering a mobile installation. Now where would the quietest place be? Oh, yes. The cemetery. Really. It's on top of a hill, no electric utilities or anything like that for a good half mile in each direction! :)
 
The Noise Is Deafening  
by IW5CI on May 8, 2017 Mail this to a friend!
Every evening i had 9+30 noise from 3 to 30 MHz . It started at 20 pm and end at 06 AM. Quite every day. The day when the noise was not 9+30 i had a 9 noise that i could manage with NR and noise blanker.
After 1 month of test and investigation i found the cause of the main qrm from a neon starter in a shop 30 meters from my house.
Now the problems is solved, but i still have the second noise that is probably generated from mi neighbour TV set or his led lamps.
I hope to deal with him a solution because i like hamming after dinner.
 
The Noise Is Deafening  
by K0RO on May 8, 2017 Mail this to a friend!
I had S-6 persistet noise. Bought a $20 "all-band" chinese receiver and went hunting. Discovered that the new Lowe's LED shop lights I had installed were very noisy. I usually turned the lights on early in the morning and left them on until just before bedtime. Turned them off, checked the s-meter and noise went to S-2.
 
The Noise Is Deafening  
by KK5JY on May 8, 2017 Mail this to a friend!
Mobile operating is one option. I find that parking under a shade tree in a rural state park can provide very quiet conditions. I was in such a location over the weekend and I couldn't get the S-meter to move on the background noise on 20m, even with the preamplifier turned on. CW signals were booming in, though. :)

A spin on the mobile option is to install mobile gear in your vehicle, parked outside your condo, and remote control it from within your home. I have done remoting like this with wifi and low-power VHF radios and very basic antennas. VHF radios give you near-instantaneous audio, and the wifi can do basically everything else using remote serial ports (like Moxas) or remote relays and such. This option lets you get your vehicle far enough away from the building that the noise level should fall to a manageable level. It probably won't be perfect, but it should give you several dB of improvement to get the antenna outside the building.

As an extra bonus, vehicle mounted antennas can be substantially larger than indoor antennas. :)

Also, make sure you run with PRE off and ATT on. I'm amazed how many guys run on 80m or 40m with the preamplifier on, connected to a resonant antenna. Modern radios just don't need it, and you would be surprised how well you can hear people if you just knock the noise down (whatever level that is) enough to make the S-meter move less than S-2 on background noise. I used an MFJ step attenuator on my K3, and it made the bands sound MUCH better.
 
RE: The Noise Is Deafening  
by AC7CW on May 8, 2017 Mail this to a friend!
"Perhaps try operating a remote station using RemoteHams.Com software. There are many HF remote stations available to use. It's all free! Joe N3HEE"

Yeah, that looks great, long list of stations but they are typically club owned and don't accept members that aren't actually physically in the club. You can rx on most of them but no actual operating. I'm in a club that has a remote in a low noise location and I do like it, but to me, it's just not a full substitute for owning a station.

There are some rentable remote stations though, and some are spectacular and in spectacular locations. I ran across one that was in Eastern Europe, had a big rotatable yagi, amplifier, etc... cost was a few hundred $/month and you had to share it with other users... Others are $5/hour and up and no matter how much you pay you still have to deal with internet latency...
 
RE: The Noise Is Deafening  
by G3SEA on May 9, 2017 Mail this to a friend!

Maybe ECHOLINK/IRLP,FUSION,DMR,DSTAR Systems will allow to stay in the hobby until that law you mention is passed or you move.
There are many interesting Nets and hams in your situation on these systems.

G3SEA/KH6
 
RE: The Noise Is Deafening  
by N4OI on May 9, 2017 Mail this to a friend!
Elecraft K3 with NR set to F4-4; RadioSport headphones; antenna impedance matcher (tuner); patience

73
 
RE: The Noise Is Deafening  
by N0YXB on May 9, 2017 Mail this to a friend!
Lots of noise in my slice of suburbia too. Fortunately there the digital modes make HF operation possible.
 
The Noise Is Deafening  
by K9CTB on May 9, 2017 Mail this to a friend!
Just another humble opinion. Nobody asked me, but as modulation schemes change and bandwidth is no longer a concern, the noise floor on our bands will rise. Just a fact of life. If we thought "QRM fighting" techniques were good back in the day, we are about 20 years behind doing a serious re-think. When US radio spectrum users must deal with interference, including that which may cause undesired operation ... yet Russia can shut down US shortwave broadcasts because they say they interfere with their "fixed service" - you can see the problem. It all revolves around enforcement funding drying up in favor of buying votes. All that free money has to come from someplace and stealing from veterans and Social Security just ain't enough anymore. Like veterans and elderly, amateur radio operators ain't a voting bloc anyone has to worry about. :)

73,
K9CTB
 
RE: The Noise Is Deafening  
by KC3NG on May 9, 2017 Mail this to a friend!
"as modulation schemes change and bandwidth is no longer a concern,"

Goodness is this post ever ill informed. Bandwidth will always be a concern.

Lately I've had noise problems on 75. The power company was here today and witnessed the problem. The condx had been right for a couple of days, My problem was reaj and is an HV line problem, Thanks Mike and Pepco. Im hoping the problem will be gone within a week.

Renee KC3NG
 
The Noise Is Deafening  
by KD6VXI on May 9, 2017 Mail this to a friend!
A few ramblings:

Last year a broadcast industry group sent out a petition and request for information to everyone they could find who had been a victim of interference. It hit every major ham website, and the responses, from what I hear, where abysmal from us. BUT, industry IS aware that background noise levels are killing them, as well, and they are starting to get the ball rolling. Who cares. My neighbor isn't going to throw away a plasma TV he paid over a thousand dollars for, not until it dies.

Most hams today have no idea you run with the att ON and pre OFF. Yes, this is true. Unplug your antenna. Turn the attenuator on and preamp off. Plug in your antenna. Noise level go up? OK, cool. The benefit list is many, but less overload, noise levels of yesteryear, ACCURATE S meter readings, not 599 to EVERY signal.

If your noise level doesn't go up, kill the attenuator and get a copy of the ARRL antenna handbook. Junk the G5RV or 43 foot vertical with no radials and build an antenna that has some actual signals being caught. Capture area is magic.

Get RID of the OCF antennas. There is not one antenna I can think of that would be better for noise propagation than an OCF unless it's an OCF vertical.

You need 10kohm or more of choking impedance AT THE FEED POINT / balun of that antenna. And, I'd run another common mode choke where your coax comes in to the house. The OCF is one of the best noise magnets ever. Runs neck in neck with a vertical with zero common mode choking at ground level.

For choke info, Google Jim Brown choke cookbook. It's the bestester one, Steve g3txq (iirc) also has one that is very similar to Jim Brown's.

Make sure your power supply green wire ONLY connects to the chassis of your power supply, and that negative and chassis are NOT tied together. Otherwise, EVERY noisy apparatus that shares common ground will be present in your radio.

Some say use a DC grounded antenna, but the jury is out to me on this for noise suppression. I have to, because of wind and moisture (or lack of) causing static buildup.

Once all these things are done, put your radio on a 12 volt battery and kill the main circuit breaker in your house. Noise go down? Keep hunting for the offender, circuit by circuit. No, it didn't? Your lucky!

These are the first things to try. Running around your neighborhood looking like Dick Tracy doesn't help much if your installation is lacking.

--Shane
KD6VXI
 
RE: The Noise Is Deafening  
by ZENKI on May 10, 2017 Mail this to a friend!
Some good points. However nothing is going to save you when you have a items made in China that have fraudulent EMC markings on them. Lets concentrate on the law enforcement aspect of this debate. Government agencies not doing their job properly.

Where do we begin? Grown Lights, crap solar inverters, LED lights, Plasma TV, inverter battery chargers, DSL jammers, Walwarts with no filters. Ebay Laptop charges that routinely put out 20db over S9 hash. I can go on and on. But the bottom line is that these manufacturers say that they "comply" with the various EMC laws for conducted and radiated emissions and they clearly meet no international EMC standard.

I measure dozens of faulty products from my local ham club using a LISN and calibrated EMC antennas. Let me tell you that your antenna design, common mode chokes and the latest 10,000 dollar wonder rig is not going to save you if if your neighbor installs a any one of the above near your antennas. A classic example is the LED 50 watt floodlights on Ebay from China. They will wipe out HF from 160 through to 6 meters with 40db over S9 noise.

"Few Ramblings"
 
RE: The Noise Is Deafening  
by N3HKN on May 10, 2017 Mail this to a friend!
Since I started this - I am sitting here with a perfectly serviceable, but old, Yaesu FT-707. It is connected to an attic dipole 24ft per side fed with a 4:1 balun. The feed-line is 25ft of 9913 to a Dentron KW tuner.

This is the third transceiver I have bought since I decided to once again focus more on Ham Radio. I began with a CB "walkie-talkie" a very long time ago. In fact way before before that I sat in the basement with a homebrew transmitter illegally calling CQ. A station in California (I am near Pittsburgh) came back to me and for several years I lived in fear that the FCC would come and get me.

So, the first transceiver, for my current re-activation of interest, was a SoftRock transceiver (1 Watt). Noise still ++. So, I went thru the in-house power-down thing but still noise on 40, 30, 20. So I bought an antenna that I could put on the deck below my 2nd story room. It was a joke. Noise, horrible performance/swr. Well, how about an end-fed dangling out the window with 24ft of wire. Still noise and poor performance. I was finally told that I needed at least 30 ft of feed-line. So I added more coax and it helped the SWR but not the noise, since the added feed-line dangled from the window in a loop beside the building. I sold the antenna and the transceiver and decided to seek other hobbies.

After a week of agonizing over the decision, since Ham Radio was my primary passion, I bought the 707 for another go. This time I also bought a phased noise canceler. I spent hours following the recommendations of two equal sources (signal and noise) which the device would phase shift and cancel out the noise. As mentioned the results were spotty and not reliable and the device was returned. When I lived on 2 acres with a quad I also had a canceler and it worked but no 2 acres now.

Here I am with a useless FT707, some wire in the attic, and my favorite hobby still a waste of time and money. My next option is to build a loop antenna set it on the deck in the hope that its well known rejection of noise will be sufficient for the reasonable enjoyment of Ham Radio.
 
The Noise Is Deafening  
by WA3SKN on May 10, 2017 Mail this to a friend!
My suggestion is to find and fix the trouble.
If it is S7-9, it is in all probability in your dwelling and can easily be filtered.
Build a directional antenna for the frequency(ies) and start DFing the issue.

-Mike.
 
RE: The Noise Is Deafening  
by W3TTT on May 10, 2017 Mail this to a friend!

"...by KD6VXI on May 9, 2017...A few ramblings:..."

Can anyone with an EE degree and/or more experience verify the steps listed by KD6VXI? It seems to me that many of the rambling steps have little or no basis. Can anyone confirm the advice?
 
The Noise Is Deafening  
by W3WN on May 10, 2017 Mail this to a friend!
Well Dick, there's actually a relatively simple solution for you.

Join the Steel City ARC and, as a member, have free access to their remote station.

I think Skyview either has one as well, or are (were) looking into it. Radio Free Bob could give you a better answer on that, my information may be out of date.

Sadly, these are about your only solutions... unless you choose to move. Your antenna choices are limited by many factors, including the details of your rental agreement and permission (or lack thereof) of the property owner or management company.

RFI/EMI is only getting worse... as cheaper and cheaper devices continue to flood the US market, and they remain cheap because some corners are cut, which includes the few pennies worth of components (in bulk manufacturing) that RFI mitigation would require. Your neighbors may not even know that their devices emit EMI -- or care. Or the source could be external to the buildings, as solar arrays are popping up around the area, and some of their DC-to-AC converters are dirty from an RFI/EMI standpoint (at least one installer, Solar City, appears to be either clueless or uncaring, which is one of the reasons why we decided to pass on their offer)

At least you have some local options. Many are not as fortunate.
 
The Noise Is Deafening  
by KE4ZHN on May 10, 2017 Mail this to a friend!
You can have the finest station money can buy but it won't help you if the neighbor fires up a stick welder in his garage. We are at the mercy of our surroundings.
 
RE: The Noise Is Deafening  
by N9AOP on May 10, 2017 Mail this to a friend!
Poles???
Do they still place neighborhood distribution lines on poles like they did in 1940?
Art
 
RE: The Noise Is Deafening  
by AJ4SN on May 10, 2017 Mail this to a friend!
Although I don't have an EE degree, the suggestions by KD6VXI are sound based on the experience that I have had and based on the theory that I understand. I live in the most densely populated county in Florida, and RFI is a fact of life.

Turning off the pre-amp and the attenuator can help.
Verticals are somewhat noisier antennas.
A choking impedance at the feedpoint can help.

After trying the suggested remedies, I would also see if one of the noise cancelers helps. I have used and built several, and they are helpful.

Hang in there!

73, Stan

 
The Noise Is Deafening  
by W6AAJ on May 10, 2017 Mail this to a friend!
I have had good success with the MFJ-1026. As others have mentioned, getting the "noise" antenna right and VERY careful tuning are the key.

73
 
RE: The Noise Is Deafening  
by K6CRC on May 10, 2017 Mail this to a friend!
'These are the first things to try. Running around your neighborhood looking like Dick Tracy doesn't help much if your installation is lacking.'

In my case, the Power Pole insulators were 95% of the noise I was hearing on lower bands. PG&E sent out a contractor (and a ham) to verify. Cleaning and/or replacing a couple of insulators and taps fixed it.
I have several small noise sources, grow lights for constantly stoned neighbors and an old instant-on water heater next door. But, those are knocked down pretty well by rig NR and NB settings.
I would suggest running the rig off a battery with main household breaker cut off to check for household noise of course. But, at least in urban/suburban areas, look to the power poles.
 
RE: The Noise Is Deafening  
by N3HKN on May 11, 2017 Mail this to a friend!
I have wondered about the value of the battery operation. If you disconnect the antenna and the noise drops to expected values is that not sufficient to prove that the noise is due to local radiation, or is there some component I am missing?
 
RE: The Noise Is Deafening  
by AA4PB on May 11, 2017 Mail this to a friend!
The benefit of battery operation is that you can kill power to the whole house and verify if the noise generator is in your own house or not.

My personal experience is that 99% of the noise is generated by arcing insulators and connections on the power poles. I've had very good luck with getting Dominion Power to come fix the problem once I identify the pole(s) having the issue.
 
It might be those new, white HID street lamps...  
by ON4AA on May 11, 2017 Mail this to a friend!
Utility companies are replacing at a fast pace traditional orange sodium-vapour lamps with more efficient, white light, metal-halide high intensity discharge (HID) street lighting fixtures.

Unlike sodium-vapour lamps, metal-halide HID gas discharge lamps require a high voltage power supply —called electronic ballast— that is typically a couple of kilovolt switched at 100–400 Hz with a square wave pattern...

More about this over here:
http://www.eham.net/articles/38804

73 de Serge, ON4A
 
RE: It might be those new, white HID street lamps...  
by N3HKN on May 11, 2017 Mail this to a friend!
My electric service is underground. But pole/feeds are about 200ft away...
 
RE: It might be those new, white HID street lamps...  
by W4KVW on May 11, 2017 Mail this to a friend!
I can't relate.I live in a small town & my S-meter on most days lays on the 0 or maybe an S-1.It's Rare that I get a noise level above an S-5 at any time of the day or night.I am running both pre-amps in the ICOM 7600 into my Mosley 5 band yagi. I am also running an external Pre-amp on my ICOM 271A & most days the noise level on it is around an S-3 or S-4.It's great living out here away from the big city lights,noise,& crime.Can't imagine ever putting myself in the closed in box of a Condo or an HOA where it takes away my freedom.We must all live with our choices so looks like yours are getting the best of you on being able too operate your station so maybe it's time too make another choice & this time a wise one or learn to live with the one you have already made & accept what comes with it.

Clayton
W4KVW
 
RE: The Noise Is Deafening  
by W1PJE on May 11, 2017 Mail this to a friend!
> Get RID of the OCF antennas. There is not one antenna I can think of that > would be better for noise propagation than an OCF unless it's an OCF
> vertical.

I don't understand the technical basis behind this statement. Can you explain it in more detail?

Thanks -
73
 
RE: The Noise Is Deafening  
by ON4AA on May 11, 2017 Mail this to a friend!
> Get RID of the OCF antennas.
> There is not one antenna I can think of that would be better for noise propagation than an OCF unless it's an OCF vertical.

I am afraid two entirely different things are getting mixed up here. Operating an OCFD with an ineffective balun and/or lacking a sheath current choke will allow for sheath current of your own emitted signal to creep back to the shack causing all kinds of RFI.

Placing one or more sheath current chokes at the right spots along the coax will effectively eliminate this RFI problem. See http://hamwaves.com/chokes for details.

However, the topic of this thread is about external QRM and OCFDs do not behave any different towards QRM than center fed dipoles.

(...and yes, I am a MSc in EE)

73 de Serge, ON4AA
 
RE: The Noise Is Deafening  
by ON4AA on May 11, 2017 Mail this to a friend!
@Chav, LZ1ABC

I am curious to know what loop configuration you are using. A crossed coplanar loop, a single fat loop, orthogonal loops or maybe the crossed four-quad?

http://active-antenna.eu/tech-docs/3_ActiveAA_Antena_11.pdf

73 de Serge, ON4AA
 
RE: The Noise Is Deafening  
by W1PJE on May 11, 2017 Mail this to a friend!
> I am afraid two entirely different things are getting mixed up here. Operating an OCFD with an ineffective balun and/or lacking a sheath current choke will allow for sheath current of your own emitted signal to creep back to the shack causing all kinds of RFI.

> Placing one or more sheath current chokes at the right spots along the coax will effectively eliminate this RFI problem. See http://hamwaves.com/chokes for details.

> However, the topic of this thread is about external QRM and OCFDs do not behave any different towards QRM than center fed dipoles.

Thanks Serge. That clarification is consistent with Maxwell's laws, radiation resistance, antenna current pattern theory, and EM theory.

There is a further confusion/conflation here: vertically polarized radiation does propagate in the presence of a ground plane, but horizontally polarized radiation has more trouble. So a vertical antenna will have more QRM, but again it has nothing to do with OCFD design.
 
RE: The Noise Is Deafening  
by ON4AA on May 11, 2017 Mail this to a friend!
> Vertically polarized radiation does propagate in the presence of a ground plane,
> but horizontally polarized radiation has more trouble.
> So a vertical antenna will have more QRM.

You are absolutely right, Phil. Very nicely put!

I have also been writing about this: http://hamwaves.com/vertical-horizontal/en/index.html#polarisation-noise-at-hf

It is also the reason why people are obtaining good QRM immunity from wide-band active small magnetic loops mounted close to the ground — not to be confused with tuned magnetic loops!

Here is another example by PA3GZK: https://pa0fri.home.xs4all.nl/Ant/Active%20antenna/Active%20receiving%20%20loop%20antenna%20eng.htm

Notice the HID street lamp in the background of one of the pictures!
 
Made-In-China JUNK  
by VE3CUI on May 11, 2017 Mail this to a friend!
My son installed those pretty-looking under-the-cupboard 3-level touch-control halogen lights in the kitchen here both at home, as well as at our cottage. One day I'm hammering away on 40 CW with the Vibrokeyer, & I notice that the lights are blinking "...off-low-medium-bright-off-low-medium-bright" in direct sequence with my code characters…!

Then, a short while later, I discovered the source of the noise whenever I was in receive mode --- yup, those insidious lights generated RFI when in ANY "on" position, as well as being susceptible to RF.

The solution in BOTH locations…? I PHYSICALLY UNPLUG THE DAMN THINGS before going on the air.

But I pity the woe-begotten Ham living in the heart of suburbia, literally SURROUNDED by this Chinese garbage!
 
Made-In-China JUNK  
by VE3CUI on May 11, 2017 Mail this to a friend!
My son installed those pretty-looking under-the-cupboard 3-level touch-control halogen lights in the kitchen here both at home, as well as at our cottage. One day I'm hammering away on 40 CW with the Vibrokeyer, & I notice that the lights are blinking "...off-low-medium-bright-off-low-medium-bright" in direct sequence with my code characters…!

Then, a short while later, I discovered the source of the noise whenever I was in receive mode --- yup, those insidious lights generated RFI when in ANY "on" position, as well as being susceptible to RF.

The solution in BOTH locations…? I PHYSICALLY UNPLUG THE DAMN THINGS before going on the air.

But I pity the woe-begotten Ham living in the heart of suburbia, literally SURROUNDED by this Chinese garbage!
 
RE: The Noise Is Deafening  
by W1PJE on May 11, 2017 Mail this to a friend!
Nice examples, Serge. I think the combination of active RX antenna loop and separate TX antenna is a very good one. This gets back to much earlier days in this hobby when having separate TX and RX units was much more common (when people built their own crystal controlled transmitters).

By the way, if you want to use a loop for transmit, remember that it is inherently narrowband (high Q) in that application, and therefore requires tuning when you move more than a few kHz off frequency. A number of designs are available but they often use expensive vacuum variable capacitors. (Recall that a mag loop has a radiation resistance in the milliohm range!)

But some people are being clever and using air variable caps immersed in nontoxic dielectrics such as motor oil, paraffin oil, and similar. This also keeps people away from the high voltages on these caps. (Stay away from transformer oil!!) Experimentation may find you a good high-dielectric oil, and amateur work should be about experimentation.

An excellent example of the above is here: https://www.nonstopsystems.com/radio/frank_radio_antenna_magloop.htm

73 to all,
W1PJE
 
The Noise Is Deafening  
by KD6VXI on May 11, 2017 Mail this to a friend!
ON4AA, I confused nothing.

You'll notice I said two. One at the shack, one at the feed point.

I did not confuse terminology, either.

The off center fed, being a SEVERELY unbalanced antenna is HIGHLY susceptible to common mode currents. BOTH common mode on rx and TX.

TX, this causes the outside of the shield to act as a counterpoise, or ground return, of the antenna..... This can cause rf to return all the way to the rig and is sometimes the cause of 'rf in the shack', lip burns with metallic mics, etc.

On rx, if the entire feedline is not divorced from the antenna, you now have RF INGRESS. You now have a wonderful noise magnet routed along the eaves of the condo, etc. The noise will couple to the outside of the shield, to the unchoked (or simple balun included) feed point and in the case of a balun (dependant on design) it can be directly coupled to the center conductor. A feedline choke at the feed point reduces or eliminates (with enough choking Z) the problem.

The noise will also be coupled along the inside of the shield as well. This is ANOTHER reason you want a choke at or just before the feed point. It PREVENTS the common mode noise on the outside of the coaxial braid from EVER reaching the feed point.

Same thing for using one at the shack entrance.

A 'shack ground' doesn't eliminate the problem, either. It dumps the residual rf into the earth, but I prefer mine to be dumped into then antenna.

Most of this is basic antenna theory, but for anyone who disagrees, I refer you to published works by K9YC and G3TXQ (hexbeam), as well as the ARRL antenna handbook.

K9YC is actually (re) writing the part of the ARRL handbooks dealing with balun and chokes. His PDF file below is the culmination of years of vector network analyzer work with, you guessed it coaxial chokes, balun, choking mechanisms, etc.

http://audiosystemsgroup.com/RFI-Ham.pdf

http://www.karinya.net/g3txq/chokes/

The case studies of hams who have read one or both texts above, gone on to choke off their feedline and then reported one to multiple s unit DECREASES in noise levels is many on the contesting rfi and towertalk reflectors.

Hope that helps. Hope it helps the original person posting the question as well as the person who wrote the 'article'.

Simple physics here guys. And to allay any questions, Jim is also a papered engineer. And his choke cookbook above is peer reviewed. For those doubting, I refer to the rfi and towertalk sites.

--Shane
KD6VXI
 
RE: The Noise Is Deafening  
by LZ1ABC on May 11, 2017 Mail this to a friend!
@Serge, ON4AA

I am using the simplest configuration - a single 1 m loop.
It does the job and it really opened the bands for me as previously I was unable to hear anything below 14 MHz.

You can check it here - boring video:
https://www.youtube.com/watch?v=UK49zCv2UPg&t=367s

73 de Chav/lz1abc
 
RE: The Noise Is Deafening  
by ON4AA on May 12, 2017 Mail this to a friend!
Thanks for the info, Chav.
This video comparing an active loop to dipoles is equally impressive:
https://www.youtube.com/watch?v=S4nFvetVVbQ
 
RE: The Noise Is Deafening  
by K9CTB on May 12, 2017 Mail this to a friend!
@KC3NG: Because you disagree with me, "I" must be misinformed? That's pretty close to arrogant venom, which feeds the problem with little concern toward solving it. If you look at the noise level creep in the past 30 years, which means you have to be cognitive for at least that long, you pretty much see the problem. It's the reason for the article. Spread Spectrum for one example, was an attempt to get around single-channel interference. It worked well until so many commercial (think ISM) modulation schemes used it. It was fine until it left the UHF domain and crept into HF. And that's just one example. When chirp technology uses HF bandwidth in 1 MHz chunks, and every kid and his mother uses the some form of the mode, it's gonna raise the noise floor. The comment that "bandwidth is no longer a concern" was hyperbole and humor, and to Amateurs it WILL always be a concern. To restate without making you angry, we're gonna have a rising noise floor by the very nature of technology. The only way to deal with it, imho, is to get control on the "bad players" who add to the mess we're in by operating illegally. Doing so would slow down the damage and prolong the usability of the bands by amateurs and other users with no political influence. How's that? I certainly mean no disrespect to amateur users, but we are here only because of our ability to help in disasters, convey international goodwill and hopefully take care of each other (police ourselves). But we need backup!

73,
K9CTB
 
The Noise Is Deafening  
by KD8TUT on May 14, 2017 Mail this to a friend!
Just an observation...

Based on my few years as a ham, and the reactions of urban hams who visit my station- it's hard to imagine operating in an urban environment. Or trying to do it without phase cancellation and some pretty finely tuned antennas.

Even in my rural/sparse resort area, there's some noise that I need to deal with by creating directional nulls.

But in an urban environment it comes from every direction.

Knowing what I know now about noise- I'd probably not even attempt it in an urban area.
 
The Noise Is Deafening  
by KK4YDR on May 16, 2017 Mail this to a friend!
DX Engineering Magnetic Loop for RX and TX on whatever you want.

Should cut the noise in half or more.

I use active vertical antennas and they work great. I have had lots of problems with DX Engineering's NCC 2 phaser but they have been there to take care of me VERY GOOD indeed! I have made a few sour comments about them simply out of frustration of having the equipment go bad twice in a row not of my fault but they have bent over backwards for me so I will NOT stop using them or their products. DX Engineering is a great company and their noise phasing equipment is actually HIGHLY regarded and excellent in performance.
 
The Noise Is Deafening  
by VA3WAO on May 16, 2017 Mail this to a friend!
My first suggestion is to try MFJ's 1026 noise cancelling filter. I have watch some video's on it had had it demonstrated to me live and it is something to watch work, instant up to 60db null on noise. At $200 bucks in a noisy environment, I would say it's an investment well worth it.

While I don't own one myself, one could be in the near future sitting in my shack. I know many of the ham elite snobs will look down their nose at MFJ ... but if it works??? P.S. use and external antenna and not the extending antenna, you will get much better noise reduction.
 
The Noise Is Deafening  
by N0AH on May 16, 2017 Mail this to a friend!
Need to find a solid ground source-
 
RE: The Noise Is Deafening  
by AD5VM on May 18, 2017 Mail this to a friend!
I moved into a new house, got the station and 500 ft horizontal loop all setup, S-9 noise on all bands. I just assumed it was the utility system in the neighborhood. I'm ashamed to admit that after weeks, maybe months, I grabbed a portable AM radio and set out to find the offending power pole or neighbor that was the cause of my problem.. Turns out it was a Ryobi cordless drill battery charger in my own garage.
DOH!

I've never found a computer UPS system that didn't blast hash everywhere, and no matter what the eham reviews or the manufacturers website said, every small switching power supply I've ever tried made a bunch of RFI spikes that slowly swept across the bands.

I remember a post here on eham probably ten years ago about a ham who tracked the source of noise that had kept him of the air for years to a house two blocks away, it was an old doorbell transformer in the attic. He bought and installed a new doorbell system for the lady that lived there. Everyone was happy!
 
The Noise Is Deafening  
by K7EXJ on May 19, 2017 Mail this to a friend!
A bag full of ferrite snap-on beads took my S9 RFI down to S3.

Less than $50.

 
RE: The Noise Is Deafening  
by WA9UKB on May 20, 2017 Mail this to a friend!
Posted on QTH

Due to ongoing unresolved power line and plasma TV interference I'm selling my Flex 6500 I bought new in Nov 2014 and Maestro I bought last summer.


This has been an unresolved RFI issues sad no resolve from FCC or ARRL since 2001

Most of my General listening has been using a Flex 1500 and to capture videos of interference.
 
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