In recent months we have enjoyed a steady improvement in conditions on 20 Meters. At the bottom of the solar cycle we look forward to this, because there is not much DX coming through on higher bands at any time of the year. Late spring openings on 20 provide us with our best opportunities for long haul DX. These DX windows are especially important when a needed country is activated in a remote corner of the world, and we always hope these expeditions occur when propagation is seasonally favorable. Such exotic openings are at their best right now, and will remain good through August. A VU4 would be nice.
With 20 open late into the evening and the sun continuously low in the sky over the pole, we expect daypath bands to open up nicely - but they don't. Many of us call this "absorbtion". Even at the top of the cycle, the usual daypath bands are dead to marginal. This is because the ionosphere is cooked: it is warmed by exposure to the sun, causing molecules to thin out and MUFs to drop. With the lowbands full of QRN and 10 & 15 in the doldrums, DX activity becomes concentrated on 20.
As the ionosphere thins in the morning hours, it slows the daytime rise in the MUF and prolongs long haul DX openings on 20. These pipelines extend to the Far East, where there is an evening DX window lasting several hours. In our evening, of course, the tables are turned and we work lots of Russians. The path to the Middle East is also open. These are usually difficult paths at the bottom of the cycle.
Where the slow rise in the MUF prolongs morning openings on 20, it delays them on higher bands (if they open at all). Europe has been opening on 15 lately, but not until the afternoon. These openings have been marginal only because we are at the low end of the cycle, and are usually noticed only during contests. At higher flux levels the openings on 15 this time of year are spectacular, with big signals from Europe through the evening. With our low flux levels, we look for propagation on lower bands like 17 and 20. Daypaths are marginally open on 20, well enough to keep the East Coast busy running Europe in the WPX CW.
Though nighttime QRN levels are now kinda high, 40 is still in much better shape than 15. The DX windows aren't as broad as in winter, but much of the world is workable. There are good openings to the northeast around sunset and into the evening, and Asia comes through nicely in the morning. In the WPX there is a point advantage for lowband work, which makes this out-of-season band a very important factor.
It is June, and Field Day approaches. The Sporadic-E season is peaking for 6 and 10 Meter short skip, which seems to be at its best at the low end of the cycle.
http://www.nol.net/~ids/prop.html
E-Mail: ad5q@kb5tes.#setx.tx.usa.na or ids@nol.net