Satgen 550 HF Propagation Studies by GM4IHJ (BID SGEN550) 1999-10-09 Northern hemisphere stations are hopefully due for an interesting winter, as we head towards sunspot cycle maximum, and enjoy the best months of the year for DX. As yet the solar flux has been very irregular , with no clear sign of a bumper maximum in the new millenium ahead. But that is no excuse for not looking. Using the worldwide 28.2 MHz beacons of the North California DX Foundation ( ie each beacon has a 10 second slot in a 3 minute repeat sequence, every beacon firing in succession). You can monitor by ear or better still by AF9Y FFTDSP display on your PC. In addition you can monitor RS12/13 . The beacon is on 29.458 MHz giving some excellent signals even when far below your horizon. . Again an FFTDSP display is the best way to follow this. Noting that you can hear signals from some very odd places ie antipodeal. Indeed you can combine beacon listening, with RS12/13 tracking, in an effort to try to understand some of the terrestrial propagation anomalies revealed by the NCDXF beacons :- a. The persistence of the LU4AA beacon into Scotland b. The presence of 4S7B and ZS6DN but only rare glimpses of 5Z4B c. The excellent VK6RBP signal into GM from 1000z to 1300z most days d. The auroral returns fron RS12/13 at and below GM southern horizon One method used here it to see if RS over say point A is putting a signal into GM via a chordal hop down from the satellite skimming the ground then up to the underside of the ionosphere at point B, from whence the signal is propagated to GM. Then checking to see if the ionosphere at point B is putting any terrestrial signals into GM. Two things are clear at this time . Firstly there is excellent south to north propagation from the southern hemisphere into high northern latitudes . But terrestrial stations on or north of the equator are not being heard much in GM. Why this should be so is unclear. But there is an odd clue . A typical example of which is the strange sub horizon propagation of the RS beacon when the satellite is traversing latitudes between 40N and 10N. When RS heads south from GM at around noon, it should go below the southern horizon at somewhere near 25N. It does and its clear signal is lost . But while it is above the GM southern horizon heading south at about 40N clearly audible, a second signal comes up showing wide band auroral characteristics. This auroral signal persists long after the clear signal is lost at anticipated LOS, finally disappearing 7.5 minutes after it first appeared, when RS is over latitude 10N. Some eyebrows may be raised by this " Southerly aurora", but it is reminiscent of the effect of massive enhancement of electron levels in the ionosphere above latitude 40N, reported by Uosat 11 in periods near previous solar cycle peaks. Which may presage plenty of oblique 6m DX Europe to W and VE, by aiming ones antennas at West Africa up to noon UTC, then the Caribbean after noon UTC. Long before direct paths are available.