ARLA/CLUSTER: Primeiro QSO por "meteor scatter" nos 4 Metros em África.

[João Gonçalves Costa]

[http://tbn0.google.com/images?q=tbn:4xne-8oBxuYwBM:http://www.qsl.net/g0isw/G0ISW%2520WSJT.jpg]<http://images.google.pt/imgres?imgurl=http://www.qsl.net/g0isw/G0ISW%2520WSJT.jpg&imgrefurl=http://www.qsl.net/g0isw/g0iswstation.htm&h=551&w=677&sz=166&hl=pt-PT&start=1&usg=__nXpQT2Sohd-agn-gnRa2Zu57G2U=&tbnid=4xne-8oBxuYwBM:&tbnh=113&tbnw=139&prev=/images%3Fq%3DFirst%2Bmeteor%2Bscatter%2Bon%2B4%2Bmetres%26gbv%3D2%26hl%3Dpt-PT%26sa%3DG>[http://www.mydarc.de/dl7afb/contest/2m_omni-dipoles.jpg]<http://www.mydarc.de/dl7afb/contest/2m_omni-dipoles.jpg>[http://tbn0.google.com/images?q=tbn:RFkSu-q_aj3XYM:http://www.dd1us.de/images/oscar%2520antennen.jpg]<http://images.google.pt/imgres?imgurl=http://www.dd1us.de/images/oscar%2520antennen.jpg&imgrefurl=http://www.dd1us.de/amateur%2520radio.html&h=637&w=640&sz=62&hl=pt-PT&start=65&usg=__tn2fgDXSCb__ajsSPFM6o30ERWQ=&tbnid=RFkSu-q_aj3XYM:&tbnh=136&tbnw=137&prev=/images%3Fq%3DDirectional%2Bantenna%2Bto%2B4%2Bm%26start%3D60%26gbv%3D2%26ndsp%3D20%26hl%3Dpt-PT%26sa%3DN>
First meteor scatter on 4 metres

On 31 August 2008, Andre Botes ZS2ACP, in Port Elizabeth and Paul Smit ZS6NK, in Polokwane made what was probably the first meteor scatter QSO on 4 metres in Africa.

The two stations started at 03:00 UTC and completed at 04:18 UTC on 70,200 MHz USB using FSK441. Andre, ZS2ACP, used a modified TenTec 6m transverter running 23 Watt into a 3-element Yagi and Paul, ZS6NK, used a homebrewed transverter running 24 Watt into a 7-element Yagi.

They made another meteor scatter contact during the VHF contest on 21 September. During this contact, Andre used a 5-element Yagi.

FSK441 software is designed for high speed meteor scatter communication using the brief "pings" of signals reflected from the ionized trails of meteors about 100 km above the earth's surface. Such pings are typically a few dB above the receiver noise and may last from ten to a few hundred milliseconds. By using these brief pings, FSK441 facilitates QSOs in the range 800 to 2 200 km in the amateur 2-metre and other VHF and UHF bands.

The WSJT FSK441 meteor communication software was developed by Jo Taylor K1JT, a 1993 Nobel Laureate in Physics for the discovery of a new type of pulsar, a discovery that has opened up new possibilities for the study of gravitation.

Jo's interest in amateur radio goes back to his teenage years. In an autobiography published at the time of receiving the Nobel prize, he wrote "Among my fondest boyhood memories are collecting stone arrowheads left on that land by its much-earlier inhabitants, and erecting, together with my brother Hal, numerous large, rotating, ham-radio antennas, high above the roof of the three-story Victorian farmhouse.

"With one such project, we managed to shear off the brick chimney, flush with the roof, much to the consternation of our parents. That incident was one of many practical lessons of my youth, not all absorbed in the timeliest fashion, involving ill-advised shortcuts toward some goal."

Congratulations to Andre, ZS2ACP, and Paul, ZS6NK.

Fonte: The South African Radio League<http://www.sarl.org.za/Default.asp>
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