No surprise to anyone, Flex filters in digial mode are simply second-to-none.
Last night (local) on RTTY, I worked EY7AD for a new one on RTTY. There as polar flutter that was a challenge but I still did get a decode. Only my 2nd Tajik QSO ever (last one was in 1990!) And I did not have any interference from nearby signals. Just set the SDR DIGI-U filter width to 300 Hz. No sweat. Call him, and he's IN THE LOG.
My best guess is over the pole (if not true, then certainly magnetic!). I have two hex-beams, one pointed 350 and one pointed 070, both at 40 feet high. The signal was much stronger on the hex pointing north...from here in NC that's 023 degrees true...I presume that if the path were bent then it would have not had as much flutter and would have been stronger on the E pointing hex.
I heard EY7AD on RTTY 2 weeks ago but had to QRT before I could work him. The interesting thing is that after I worked EY7AD, I had a UA4 calling me on the EY7 frequency. I QSY'd up and worked him, and then worked several very strong UA3 stations as well.
At first I thought it might be that the EY7 signal was bent path along the UA3 route. But after I worked EY7AD, I did not hear anyone calling him. Not even the UA stations. So I am guessing that he was not audible to UA3. Certainly, Tajikistan is uncommon on any mode and esp RTTY, and I feel certain that if they could hear him they would have called him.
73 and good DX!