PROPAGATION - by AD5Q HOUSTON, TEXAS -- FEBRUARY 1997


We are now past mid-winter, a time when night path conditions return to 20 Meters during sunspot peaks. For us, these conditions will not be seen until late April. While many are watching the sun for signs of the new cycle, others are at their radios finding paths to needed DX on different bands or at different hours. We all found a path to Heard on 20 by taking advantage of the long haul pipelines at the beginning and end of the day. These occur mostly during daylight while the sun is low in the sky, but can extend across areas of darkness in the southern hemisphere where night paths are seasonally open. Contacts on the other side of the world are made by exploiting these opportunities.

There is little activity on 10 & 15. North-south paths are open daily, and on 15 we can work east as far as Africa. But it is the northern latitude paths that populate the band, and no seasonal relief is expected until the fall. The daypath to Europe is on 20, which remains marginally open for several hours beyond its greyline peak in the morning. The ARRL DX Test is coming, where daytime activities include chasing Caribbean mults on 10 & 15 and listening to the east coast run Europe on 20. Marginal conditions are expected to Europe on 15.

A rich variety of DX openings can be found on 40. The best path to Europe begins in late afternoon while it is still daylight in Texas. This opening extends further into the evening on the east coast. I have no idea what 40 sounds like from there in a contest, but it must be nice. Later in the evening the MUF drops below 7 MHz at high latitudes and european activity drops. On most evenings we find propagation across lower latitudes, such as to Africa with its large pileups. There is also a sunrise peak sweeping across Russia at this time, but polar paths are difficult on 40 so most signals are weak. After midnight this opening moves across the rest of Europe - as the Pacific opens up and darkness approaches Japan. Access to Asia broadens through the pre-dawn hours and peaks after sunrise. There is also a brief high latitude short path pipeline along the northern greyline (into Scandinavia and Russia from W5) which many without directional antennas mistake for long path. Actual long path openings occur in several directions, and the west coast knows them best.

On lower bands, the best opportunities are at sunrise and sunset peaks. The european peak is after midnight, but the stronger EU stations can be worked earlier in the evening (in pileups) when everybody is stalking the bands. After midnight, the band is quieter, the DX is louder and the east coast is mainly asleep :-)

http://www.nol.net/~ids/prop.html
E-Mail: ad5q@kb5tes.#setx.tx.usa.na or ids@nol.net