January, 2007

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TV on a Light Beam
It may sound like science fiction, but a group of amateurs in Australia has sent a slow-scan TV image over a 13-mile path using modulated light on 474 THz. According to Newsline, analog SSTV pictures were exchanged back and forth along the path, as well as lightwave voice contacts among team members. A .wav file was also sent using JT65, but had not yet been decoded as of press time, so it was not yet known whether that mode had been successful as well. Further experiments are planned.

Experiment appears to support Marconi
A trans-Atlantic radio experiment appears to have backed up Guglielmo Marconi's claim that he was first to receive a wireless radio signal across the Atlantic. The Italian inventor famously confirmed that he had received a radio transmission sent from Poldhu in Cornwall to Newfoundland in Canada in December 1901. This was the first time that a radio signal had been copied across the Atlantic. But sceptics have long doubted whether Marconi actually received the signal. Some claim that the three faint clicks -- Morse for the letter S -- that he claimed to have copied could have been nothing more than background noise. Others point to the fact that he claimed to have detected the signal at a peak daylight hour when absorption of low frequency radio signals by the Earth's ionosphere is greatest. To resolve the issue once and for all, a group of radio amateurs from both sides of the Atlantic decided to re-enact the legendary transmission. If they could copy signals across the Atlantic in the same way that Marconi did in 1901, then that would provide convincing evidence that the legendary Italian’s claim was correct. The Poldhu Amateur Radio Club in the UK and the Marconi Radio Club in Canada decided to carry out the experiment now because solar conditions currently are similar to when Marconi made his famous reception. From the start of November, the Poldhu Amateur Radio Club has been using a 160m beacon -- GB3SSS -- to make regular two-minute transmissions on 1,960kHz. Radio amateurs in Canada have in turn been trying to copy and analyse the transmissions. And now the first results from the experiment are coming in, and they seem to indicate that Marconi’s claim was an honest one. Indeed, Jeff Briggs, a ham radio expert who previously doubted Marconi achieved the feat, is now convinced that the Italian did. He managed to detect a signal sent from Poldhu at his receiving station in Canada. He said: "I'm not undecided anymore. I'd be willing to bet some chips on Marconi. "The experiment into Marconi’s famous reception will continue until February next year. [RSGB]

W1AW to change 80-meter digital transmission frequency
Effective December 15, in response to rule changes resulting from the "omnibus" Report & Order (R&O) in WT Docket 04-140, ARRL Maxim Memorial Station W1AW will change its 80-meter digital transmission frequency to 3597.5 kHz. The expansion of the 75-meter phone band to 3600 kHz makes the change necessary. W1AW will begin using the new frequency starting with the regularly scheduled 2300 UTC digitalbulletin on Friday, December 15. A possible change in the W1AW 80-meter CW frequency is under consideration.

January, 2007

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