Timewave AMC-4 Noise Canceller
I have played with phased antenna arrays to try to defeat the awful QRM which surrounds me in the gritty city. For a while I used the MFJ-1026, but un true MFJ fashion it abruptly failed one day. I like this one better anyway. It has a simpler layout, with only three knobs instead of four. I think it does a better job. As with any array, your performance will greatly depend on your receive antenna. One note about that: it takes a 3.5 mm RCA plug. You can find adapters.
Check out the Timewave AMC-4 Noise Canceller!