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Random Antenna Musings and Power Line Noise
23 July 2014 | by As I have shared in the past I have a 66′ dipole in the attic fed with ladder line. I live in a HOA controlled neighborhood so my antenna options are pretty limited.
Last night I set WSPR up running 2 watts on 20 meters. Started about 2200 UTC. Wow it really seemed open. My 2 watts was spotted multiple times into Europe, Alaska and all over the USA. This antenna does not have a problem getting out.
The problem with my antenna setup is on receive. I have minimum S5 noise on 40 and 30 meters. Typically S7 on 20 meters. Interestingly enough 15 is quieter and 10 meters is typically S2 or so. The noise is static with some noticeable “crackling”.
Last night on WSPR was a great example. I was getting heard ALL over, but I was only decoding about 2 or 3 stations – all in the USA. Also on PSK31 or JT-65 I see guys working DX that I can’t even here or see on the waterfall – my noise level is just too high.
Sometime soon I am going to cut all the power to my QTH and see what the noise level is. If significantly reduced, I will see what I identify as noise sources in my QTH.
Beyond that, less than a 1/4 mile as the crow flies I have identified some very noisy power lines. They are so noisy that it they will completely blank the AM radio in your car when you drive past them.
Here is a picture of where my house sits in relation to the power lines (my dipole runs parallel to the power lines):
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| Blue marker is my QTH – Red line is power line (X’s are noisy poles) |
I will be contacting the utility company at some point, but first I want to see how much of the noise is coming from my own QTH.
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| Red markers are trees – red line would be horizontal leg of inverted L |
5 Responses to “Random Antenna Musings and Power Line Noise”
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Look into #28 magnet wire. When you get maybe 10′ away, you can’t see it! I have a “vertical,” top fed from an upstairs window to a hook at the bottom of the house. Less noise than the attic antenna.
73 /paul W3FIS
have you tried something like MFJ 1026, it’s a switch that goes in front of your receiver to blank incoming noise at RF. worked great for me maybe you can find a local to borrow one to see if it helps. 73 dick
A couple of thoughts…
A. A magnetic loop—I use a Wellbrook ALS-1530+—with a receive switch might give you a quieter Rx noise level. Don’t know about using this setup on digital modes.
B. If I’m seeing all the trees in your yard’s landscape and assuming you could get by the HOA with this, a horizontal loop is a quieter antenna. I have one located 1″ under the edge of my roof shingles. It’s quieter that the MFJ 80/40M dipole in the attic but not a quiet as the Wellbrook loop sitting a foot off the ground!
73,
Frank
K4FMH
You are running the proposed line almost parallel to the power line. This will make for the highest pick up. The more off the parallel the lower the noise should be. Just a thought.
I’ll be curious to see the results. I have almost the same setup (attic dipole parallel to the power lines) but I have two sets of power lines to deal with. One on my street and another line on the street behind the house. Some months ago the power to the neighborhood was out for a couple hours. I hooked my rig up to battery power and the noise was gone. It was unbelievable how quiet the noise level was. Good luck!