I bought a cheap 9 dollar am BCB notch filter and tried it on the RSPDX and discovered the change was spectacular. Better sensitivity everywhere. Incredible. It helped the airspy too, especially on longwave. I heard medi-1 on 171kc and bbc on 198kc with the rspdx. My MW situation here is...severe. I am loving the rspdx now. It was fun on HF too...much better than it was. I can now recommend it strongly for dc to 2 gig. Great radio.