I had "high hopes" for my present location in regards to my radio hobby. I didn't pick the location primarily for the hobby, but it looked like it had great potential to be quite favorable for weak signal rx work. The home is located on a "rise", not a hill, but even so it has a good view of the surrounding land. On a scale of 1 through 5, I'd rate it a "4" for a radio hobby location. I moved in roughly 4 years ago, btw.It didn't take long for me to realize that this... what should have been a very favorable location for weak signal work, turned out to anything but. This location suffers from moderate to severe powerline noise that radiates a good distance from the lines. It's active nearly 24/7 with very few short intermittent breaks. I actually had far less powerline noise at previous suburban locations. That was a real "downer" for me. Time passed as I attempted and tried different antenna configurations over the months, trying to beat the noise that covered LF to above 30 mhz. This has gone on for 4 years without relief.
Making a long story short...
I purchased a "knockoff" of the X-phaser on Amazon a year or so ago. I placed it in line and ran a wire to act as the "noise" antenna. I really had no luck with it, so I just put it away for months. Gave up in defeat and tried other antenna configurations, no joy.
Time passed and I got fed up with the "status quo", so I got the phaser box back out a week ago and really devoted time (hours and a number of days) working with it.
Bottom line: I got it to work! Success! It actually knocks out the noise and allows me to hear the DX that I knew was there, but just got "buried". This location is really a solid "4" now. Even better news... The unit is rated to work from 1-30 mhz. I found out how to extend that range lower in freq. So far I have it working down into the Lowfer band. I wish I could show you the improvement it has made on 630m... what a difference. I've ordered some parts and am confident I can extend its coverage down to the 2200m band where I REALLY need it to work.
Disclaimer: This solution is not an easy "set it and forget it" situation, as I have found out. Each change in band across lf to HF will need minor "reconfiguring". If you want to just place a "box" inline with your antennas and think its going to solve all your qrm problems from LF-30 Mhz by simple knob adjustment, that's not going to happen, at least not in my experience... not with a simple inexpensive device.
I've made this post on LWCA because it does involve improving rx below 500 khz. However, since this is about the optimization of a piece of hardware more than it is about lwca activities, I don't want to answer any replies here and tie up the forum with this. If you're curious about the "particulars" of the device and how to make it work for you, you can reply to my e-mail and I'll supply the details and answer your questions. E-mail to rayb1 at gmx.com ... (trying to avoid getting spammed by bots).
Ray ... N. Central Texas
p.s. I'm sure not an expert on noise cancellation, but I can tell you what worked for me under the "working conditions" that I'm presently using.