HSCW Illustrations

- MSSOFT - Opening screen of the OH5IY MSSOFT program, the most-used shower prediction and planning program. The MSSOFT program also includes a HSCW keying program. See the 'FAQ' and 'Semi-Technical FAQ' for other comments, or download this program at:

OH5IY's MS Page

- MSSOFT - Typical screen using the OH5IY MSSOFT program for predictions and times for the 1997 Quadrantids meteor shower. This program gives predicted peak times, optimum effectivity in various directions, antenna offset and elevation, the histories of some showers, and other things. See the 'FAQ' and 'Semi-Technical FAQ' for other comments, or download this program at:


- MSDSP - Screen shot of older version (V 0.51) of the 9A4GL MS_DSP transmit-receive program, set up for a schedule between WD8KVD and KO0U/1. Note the 'ping' with QSB in the receive buffer (over the arrow). The newer versions of MSDSP have a number of new features and a slightly different screen. See the 'FAQ', 'Semi-Technical FAQ', and the 'MSDSP Operating Tips' for more information. Download the latest version of this program at:


- Screen shot of SBMS, by DL3JIN. This is a receive-only HSCW program and works very nicely. See the 'FAQ' and 'Semi-Technical FAQ' for more, or download this (and other) programs at:

Down load SBMS from here

- Look at the extreme QSB on this HSCW signal. If you have operated SSB MS during the peak of one of the major showers and happened to catch a good burst while monitoring 144.200, you have undoubtedly noticed the extreme flutter on some of the signals. There have been discussions in the past as to whether this was caused by QSB on one overdense burst, or if it was caused by several bursts overlapping in time and coverage.

As you may have noticed from decoding HSCW pings, this extreme "picket fencing" flutter is actually quite common on pings and bursts. The probable reason for this extreme QSB is because while the maximum ionization is at the head of the trail, on an overdense burst a major part of the column is ionized heavily enough to reflect the signal. The head of the column is very rapidly moving, while farther back the ionization is expanding and beginning to dissipate. Depending upon the angle of the entering meteor (as viewed by the two stations), the reflected wave will alternatively add and subtract (constructive and destructive inter- ference), as the phase varies due to the apparent motion of the head of the ionized trail.

The screen shot covers about 15 seconds, with the big peaks being about 0.4 seconds apart. It occurred on 12 April 1998 on W8WN, during a 10,000 lpm daily HSCW schedule with KO0U.