Here's the Hellschreiber transmission as monitored by K9TY. Nelson says he actually was on 15 meters, although the screen indicates 20 meters.
Dave Nelson, K9TY, ran across an interesting "new mode" while working PSK31 on 15 meters--a "Brasil" logo underlined by a swoop of stars repeated every 30 seconds or so across the waterfall display. "I think someone down in PY-land was very happy with the World Cup Final!," Nelson said, referring to Brazil's victory in the recent soccer playoffs. "I would like to know how they did it." As QST Editor (and digital modes enthusiast) Steve Ford, WB8IMY, explained, the Brazilian station used a mode known as Hellschreiber to create the effect in the waterfall display. "Hellschreiber has been around since before World War II," Ford says. "It is similar to facsimile. That is, instead of using a specific software code to send and receive text (like PSK31, RTTY, etc), Hellschrieber literally 'paints' the text on your screen using a sequence of on/off tones." Ford said the clever Brazilian operator realized that he could "paint" within the waterfall displays of PSK31 operators by transmitting the Hellschreiber tones within the PSK31 subband. The on/off Hellschreiber tones translate to areas of blue or black in the waterfall, creating the image as a result. According to Ford, most Hellschreiber (literally "bright writer" in German) activity typically takes place just above or below the PSK31 subbands. "It sounds like fast, scratchy CW," Ford said.
With acknowledgements to the ARRL 19 Jul 2002. Original URL: