As a result of on-the-air observation other satellite users planning to try FT8 or MSK144 modes via satellite are encouraged use caution using these modes and possibly avoid their use completely in light of problems.
Dave, KG5CCI wrote, “He noticed a very hard time getting into the transponder. The pass was nearly overhead, and the 3w-4w that is normally sufficient was barely cutting it. I also noticed it was ‘up and down’ alot, whereas some moments it was easy to get in, then it would be nearly impossible. There were also pockets of ‘noise’ all over the transponder, that sounded somewhat digital, but I just couldn’t place them.” Further investigation revealed that an MSK144 signal in the transponder passband was causing the problems.
Matthew, NJ4Y noted, “Experimentation isn’t the problem, too much power is. It’s bad enough on SSB, worse with CW, and killer on constant duty cycle modes like FT8.”
To gain a full understanding of the situation readers are encouraged to follow the amsat-bb message thread which can be accessed at http://www.amsat.org/pipermail/amsat-bb/2017-October/064896.html
Source: AMSAT News Service http://www.amsat.org/mailman/listinfo/ans
The Horizontal Waller Flag antenna is a produced and sold by Carlos N4IS http://top-beam.com/ The boom on this one is 44 feet long. Interlaced with th... Read more
The easy to use ADALM-PLUTO active learning module (PlutoSDR) helps introduce electrical engineering students to the fundamentals of software-defined... Read more
R&S®M3TR Software Defined Radios The challenge Today’s military missions are characterized by joint operations of multinational armed forces... Read more
Where is your signal being heard? Is your antenna working? What is the status of the band? Check out this video to learn about the PSK reporter websit... Read more
Rick Peterson, WA6NUT, in Colorado, is promoting FreeDV plus Video, a digital voice-plus-video application for HF. According to Peterson’s QRZ.com pro... Read more
Part one of our look at the Digital Modes. Read more