14 Feb 2013 – The Construction Contest Winners Speak

The Construction Contest winners spoke last evening.  There were three winners, the first was Victor, G3JNB who couldn’t be present but sent a résumé of his project, an audio filter built from two kits. The first stage provided shaping and narrowing of the audio from his small direct conversion receiver.The second stage, which was identical to the first, provided even sharper filtration to the CW signals.

The next project described was the winner of the Major Project class by Stewart, G3RXQ, who built a great circle map with LED lights to show the direction of the beam heading as derived from the signal at the rotator control unit. The LED lights were moved around the map by the use of Stewart’s own design using shift registers controlled by a PIC, which he also programmed.  The beam width could be varied to indicate a narrow beam width as found with UHF/VHF antennas or a wider beam width to indicate an HF beam.  The actual heading was indicated with a fully lit LED, while the beam width was shown by LEDs of a lower intensity.  A lone LED could be used to show the reverse or Long Path setting for each beam heading. The display was very elegant and the unit, as a whole, produced to a very high professional standard.

Rounding out the evening was a description of a Week End Special, a Desktop Active Loop built by Dennis, M0JXM. The loop itself was quite small, about 22 cms in diameter but was demonstrated receiving 40M CW signals as well as broadcast.  Turning the loop resulted in significant  loss or increase in signal strength.