Is there a best DX QTH? Probably not, but some are better than others. Draw some maps and check it out.
Radio hobbyists use a lot of abbreviations. “DX” means distance transmission. When we talk about DXing, we mean listening for or communicating with distant stations, typically thousands of miles away. QTH means location, either by name or latitude and longitude. It’s an abbreviation, or Q-code, used by radio operators for more than an century.
So, if we ask “what is the best DX QTH”, we mean a good location for hearing or working very distant stations, particularly on shortwave.
Our ability to work DX is influenced by two locations and geomagnetic activity. Locations for transmitting and receiving determine distance a signal needs to travel. You will find that the greater the distance, the more reflections off the ionosphere and ground are required. Each “hop” attenuates a signal. Depending on the ionospheric layer, hops can range from 1500 to 4000 kilometers.
DX paths that travel near the north pole can be very tricky due to polar cap absorption, effected by the auroral zone. You will notice that these paths close down when the K index gets higher (above 3). On the other hand, you will enjoy better propagation for paths that stay in mid latitudes or, even better, cross the equator.
If you want to explore rough propagation paths from your QTH, go to Azimuthal Map, Anywhere and draw an azimuthal-equidistant projection map centered on your location. You can see an AZ-EQ map centered on Calgary above. You can easily drag the center location anywhere on earth. (AZ-EQ maps are the only true maps to show both direction and distance.)
Best DX QTH is Not Calgary!
As you can see above, almost all of my DX paths to Asia, Russia, Europe, Middle East and most of Africa pass through the northern auroral zone. So, distance reception from Calgary is highly dependent on geomagnetic quiet conditions. On the other hand, paths to South America and Oceana are much more favorable for me. Distance to Australia and New Zealand is huge (more hops) but hop losses are less over salt water oceans.
On the other hand, if you draw an Azimuthal map centered on South Africa, you can avoid polar regions for most propagation paths. Unfortunately, South Africa has lots of thunderstorm static much of the year.
Europe is pretty good place for DXing because there are many more stations within shorter distances than we experience in North America. Also, more strong signal interference. It’s noisy.
So, there is probably no one best DX QTH, but some are better than others. How’s yours?