Perhaps an old story, but here again some experiences. I live in Costa Rica, about 100 meters from the HV lines looking north-west. When I beam that direction for Europe, I have between S6 and S8 noise from the lines (depending upon the wheather) wich makes life a little difficult (for me anyway, I am from Europe and like to talk to old friends overthere)
So I looked for a solution and stumbled across the website of VK3XU. He did have good results with a noise canceler system, so I tried as well. I did build the canceler described here
http://users.tpg.com.au/ldbutler/NoiseCancelling.htm with a small change, I did couple the noise antenna with a 4 turns link to L1. It took me 1 day
The coils L1 and L2 are 9 mm formers with adjustable core each with 20 turns 0,25 mm wire set 12 mm apart. Using a 2 x 470 pF variable cap from an old radio, I tune 80, 40, 20 and 17 meters
I did put a whip antenna of approx 2 1/2 meters at 60 meters from the HV lines at the fence as a noise antenna. The whip is connected via 50 meters RG58 which I will change for TV coax later. My main antenna is a Moxon for 14 MHz at 6 meters altitude approx 100 meters distance from the HV lines.
After connecting I noticed that there was not sufficient noise gain and I did put a base coil in the whip.
Results...
Unbelievable. I just turn the noise off !!
. Signals that were absolutely unreadable, come in very clearly now and are completely Q5
The circuit is really simple. The only critical part may be the J Fet. Some FETs like to oscillate. I use now a 2N4393. I did build dead bug at a non-etched print board in order to have a perfect ground. I did put some shield around the two coils to prevent coupling with L3 in the drain of the FET.
Problems with nearby RFI from HV lines , Solar systems of LED lights? this may be you low cost solution without killing the neighbors with the panels and lights!!
Thanks VK3XU, great work and very good info