The Best Method to Reduce Noise Floor

Mike VE3CKO

After getting my ticket and working 291 entities and DXCC on 6-bands, you'ld think I'd be satisfied but the problem is that I just can't get anywhere close to DXCC on 160 and 80 with noise floors of S7+ on inverted L on 160 and double bazooka, worse with verticals. Not fun hearing one side of a QSO let alone trying to get across the pond. So I found the solution and now I get S3 or below noise floor on 160m during the day and S4 on 80 with a Butternut HF9V. The solution, MOVE!

Were living in a home in the heart of the country now. Got the shack all setup as before with improvements. Boy oh boy going to have fun building my antenna farm from scratch. Lots of room for wire with tall trees for full wave 160m loop, open areas for 4 square and a couple towers. May even try an 8 circle but I think 2 bi-directional beverages will suffice. Yes, I'm excited as ****.

WF7B

Try living with an AM bc station 2000' away. Have fun.

Duane_AC5AA

You make me very envious.  Stuck here inside Austin city limits, it's noisy and no space on the small city lot for anything.  I did pick up a shielded magnetic loop to try on the low bands . . . need to find a place for that . . . 

Pierre Martel

Wow only s7! **** I envy you.. Getting s9 and s9+20 on some days. Moving was already in the plan. But it will have to wait the retirement time, in 3-4 years..

Greg K8CGS

That’s funny, “MOVE”. But you are exactly correct. I am fortunate enough to live the country life. Especially on NETS where you get a good perspective of the man made urban noise garbage out there some are complaining of, S2 is a bad day for rural living:-), other than thunderstorms.

David H Hickman

Pixel Loop hooked to the xvtr input.   It will work wonders.  Drops the floor by at least 10 - 20 DB without affecting actual stations.


https://www.dxengineering.com/parts/dxe-rf-pro-1b

James Del Principe

Well, thanks Mike, Ol' Buddy. Here I thought you had some super secret filter or set up or something. Well, let me tell you MY experience just for grins. I lived in the burbs, 3/4 miles from super high tension lines. The noise floor was very low.... S3 or so on most bands.   About one year ago we moved to the middle of no where, deep in a forest with underground utilities......   The noise is awful.... not only power line but some kind of structured hash every few KCs..... I think it is those woodland creatures. The deer, turkeys and bears have all kinds of electronics to drive me crazy! and, NO, I am not joking.....well, maybe about the bears.     73, Jim

mlstutler

I ran a 500' BOG and it was killer on 160 / AM BCB.   Compared to my 80 meter dipole I was 20 over for any station in the direction of the BOG.   They are easy to deploy too.  I noticed that signal to noise ratio was less for 80 and even less for 40.   That is where Beverage has an advantage.

Steve Roberts

Pretty dramatic solution - Moving location.
Here in the UK we bend wire all over our small back yards to do the best we can with not so much space and loads of RF noise!- Best solution is phasing two antennas to achieve back ground noise nulls & currently running an sloping "N" shaped wire antenna for 80m with get success. Inverted "V" - that's just old hat! HI.
73'S Steve

k3Tim

The BoG is interesting. I thought these were receive only though?

A problem with deplyoment is the termination / ground on the far end as there is only sand and rocks for 'earthing'.  

_..--
k3Tim

Mike va3mw

A couple of good comments here.  

In 2005 when I moved from 1 part of the city to another I had the same problem.  That started my entire remote base project and I was first on the air remote in late 2005.  Today that station has evolved with technology.

I did try a Pixel loop, but ultimately sold it as it only made a small difference but not enough to make the low bands usable.  I really wasn't impressed with it and their customer service.  This was before DXEngineering bought them.

However you do what you can to get on the air and live with what you have.  

Mike va3mw

KC0EM

I would like to offer an observation I’ve made. I live out in the country with no close neighbors and all the utility lines are buried underground. It’s a lowest noise area I’ve ever experienced. I am still often surprised by the noise I hear on 160 and 80. I have noticed tremendous differences in horizontally and polarized antennas. It often does not follow the theory that vertical antennas are noisier. It sometimes as simple as changing from a dipole or my 160 m loop to a vertical and having lower noise. I have absolutely no explanation for this violation of theory, but I do know it is worth having antennas of different polarizations to check the noise floor. It’s seems worthwhile putting up at least a couple of antennas for the low bands.

Gary Johnson

My good friend Dale Gaudier K4DG uses his K9AY loop to listen and his inverted L to transmit with power.  He can hear signals down in the weeds on the listening loop, and they can hear him running power.  He is currently quiet rural running a Flex 6500 with a 6600 coming soon.  I have room for at least 3 reversible beverages and am quiet rural too.  Closest neighbor is a quarter mile away.  Did I mention I live on a hill.  My beverages won't be on the ground though - too many deer for that, however I found 72 ten foot high T-posts at our local metal recycler for 75 cents each.  Even the deer won't run into that except at the ends.

Jeffrey Kerber, N3VE

I love my Pixel Loop!

John

Best to start with a clean up of noise surces within your own home. Then use common mode filters  wherever possible. I built up the W7IUV preamp and added a cm filter right on the input which clearly helps me a lot. Us in the UK have big problems with small gardens and noisy enviroments, not to mention topband hoggers who sit for hours ragchewing locally on 1.850 night after night running QRO power levels. In addition use a magnetic loop for receive. Sounds all easy, but it does take some effort and the results are good.

Jeffrey Kerber, N3VE

Mike, I first had my Pixel at 30 feet and it made very little difference.  I call customer service (also before DXE) and was told to mount it at 10 feet, wow what a difference! 

John

For those interested, I build a loop with a 1t primary and a 3t seconday and you can read about it at m0els.com blog
It a work in progress and I am trying to do a 3d drawing but failing miserably at it. I'll stick to pen and paper 2d...hi

KY6LA_Howard

In case you can't afford to move to a quiet location here is how I built a quiet station for better reception

https://helpdesk.flexradio.com/hc/en-us/articles/202274599-How-to-Build-a-Quiet-Station-for-Better-R... 

mlstutler

A BOG is a receive antenna .  Beverage on the Ground.  Terminating the far end will make the bog unidirectional vs bidirectional in an unterminated bog. Mine was unterminated.   I had to make my own transformer on a binocular core but that is really easy.  Used 75 ohm coax to get it back to the shack.  I should point out that soil conditions will affect the BOG.  I have clay/loam and it is ideal for the BOG.

John

One extra tip is that those of who have a flex transceiver, try reducing the receive bandwidth from 2.7k or whatever, down to 2.4k  and while you are at it, do the same for tx. No need to run wide in the QRO segment at all and it helps others squeeze in. On receive, narrowing the rx bandwidth can reduce the noise floor level by 2 s-points I have experienced.

73
John

David H Hickman

I bought mine last year. I had some really bad 20m interference and after research decided that a pixel loop was my next purchase.

I was traveling at the time and walking into the phoenix HRO and they had one used.  Bought it, shipped it home and never looked back.

Stephen Hawkins NG0G

I live out in the country in a sea of corn / soybean fields.  My noise floor on 160m in the daytime was S9+30.  I turned off all the power to my house to assure myself that the noise was not from a wall wart or anything else.  Found some dirty wall warts and got rid of them.  With a portable radio and a loop antenna I drove a lot of back roads mapping the noisy power poles.  Working with two power coops I got them to fix most of that and my noise was down to S-9.  I was then left with an S9 noise level.  I noticed that I could only hear it on one antenna, my 160m inverted L.  It is the nearest to my new garage.  Powering off the garage I narrowed the noise down to my two Chamberlain garage door openers.  Calls to them were a waste of time as their answer was "We don't hear anything coming from our openers here".  Disconnecting all the wires going to the switch by the people door and the leads going to the censors at the bottom of the doors made the noise go away.  I suspect that dirty switching supplies are using the external wiring as antenna.  I tried putting caps across each lead and caps from each side to ground that I was sure would help.  It did not.  My next step is going to shielded wire.

John

Its just amazing at how mmany noise sources there are out there in real life. One of my neighbours had an issue on his laptop amplified speakers with long 6ft leads and I cured that with two ferrite cores up close to the laptop sound ports. That killed it deader than dead.

K1UO Larry

Here is a loop that works as well as the Pixel but much cheaper.  http://www.w6lvp.com/.

I am surprised more people have not mentioned it.  I first noticed it via a uTube video by W9OY.

John

This is mine with a preamp connected and a cm filter at the preamp input. My vertical pole abt 30ft from the house and I have mobile phone masts behind me abt 300ft away
ind me 3

Brad A. Steffler

Ria,

I know some techniques and I got the power company to fix the most egregious offenders but I still have a much higher noise floor than you do. What methods did you use to find the offenders?

Brad
KE4XJ

Ria

You guys are gonna hate me. This is my daytime noise floor on my transmit phased array (2 element). Receive antennas are much lower. 

 

What's my secret? I became good friends with the electric cooperative. I pointed out a number of noise sources to them. They fixed them all. One of the linemen is a ham, and another one of the supervisors we go to the shooting range with on a regular basis. So we are good friendsThat said, powerline noise isn't much of an issue here because our wiring is underground. But stuff can still come from poles some distance away. They are VERY much interested in fixing because it costs them and the FCC can fine them.

Secondly I went around scouting every last single noise source in the house. I made my spouse and kids angry because I disconnected some of their favorite toys for a day or two. However I found really only one or two offensive items - one was a PC power supply. Bought and returned a few with noise testing until I found an acceptably quiet one. 

Third - I situate my transmit antennas some distance from the house, like 200ft minimum. Distance is like magic.

Apart from that much of it is just luck. We have wind and solar farms around here but I attend zoning board meetings and talk to engineers and find out what they are using. We even have a sign ordinance prohibiting RFI! The town also has new guidance on tower installation thanks to me.

The results speak for themselves. 9 band DXCC. Working Kosovo on 160 with 100 watts (phased array helps!) I don't really do 160 contests but I should, I guess. I just get so much flack about contesting on the weekends I really only reserve 4-5 per year. :";"You guys are gonna hate me. This is my daytime noise floor on my transmit phased array (2 element). Receive antennas are much lower. 

 

What's my secret? I became good friends with the electric cooperative. I pointed out a number of noise sources to them. They fixed them all. One of the linemen is a ham, and another one of the supervisors we go to the shooting range with on a regular basis. So we are good friendsThat said, powerline noise isn't much of an issue here because our wiring is underground. But stuff can still come from poles some distance away. They are VERY much interested in fixing because it costs them and the FCC can fine them.

Secondly I went around scouting every last single noise source in the house. I made my spouse and kids angry because I disconnected some of their favorite toys for a day or two. However I found really only one or two offensive items - one was a PC power supply. Bought and returned a few with noise testing until I found an acceptably quiet one. 

Third - I situate my transmit antennas some distance from the house, like 200ft minimum. Distance is like magic.

Apart from that much of it is just luck. We have wind and solar farms around here but I attend zoning board meetings and talk to engineers and find out what they are using. We even have a sign ordinance prohibiting RFI! The town also has new guidance on tower installation thanks to me.

The results speak for themselves. 9 band DXCC. Working Kosovo on 160 with 100 watts (phased array helps!) I don't really do 160 contests but I should, I guess. I just get so much flack about contesting on the weekends I really only reserve 4-5 per year. :";0;0;0;07/02/2018 07:20 PM;16/11/2019 11:44 PM
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19305415;7681791;19303098;8615642;0;0; https://community.flexradio.com/flexradio/topics/the-best-method-to-reduce-noise-floor?reply[id]=19305415#reply_19305415;"Inside your house? I went around with a shortwave radio pointing at various things. 

Outside I used an arrow antenna connected to an HT on HF receive mode. That's how I found poles. 

John

I do the same this side.......using a sw radio. One could also use a DF receiver. There are some cheap ones from China made for 80m and with some AAA battery's its a steal and a worth while investment.

Kevin Va3KGS

Well I have to say my noise floor just went up on all bands recently here at my QTH. 

Some people measure distance between stations in miles or kilometres, well I measure in wavelengths, and Mike, on 160M, you are about 21 wavelengths way.

Welcome to the neighbourhood OM.

A test with Mike last night on his 160M full wave loop, with 1W output, he was 30 over at my QTH.  I'm sure when the loop reaches that final height you'll crush the locals.

BTY Mike, I'm not going to tell you how much I charge to install towers yet.

Cheers OM,

Kevin, Va3KGS