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Caution Urged in Using High Duty Cycle Digital Modes on Satellites

10/27/2017

Satellite enthusiasts planning to try FT8 or MSK144 via satellite are being urged to use caution or possibly to avoid digital modes altogether in light of problems being blamed on the modes’ high duty cycle. Stations have reported problems getting into satellite transponders, even during favorable passes, which were traced to digital-mode signals in the transponder passband.

AMSAT News Service quoted an AMSAT-BB post (full thread) by Matthew Stevens, NJ4Y, who cited his recent experience with FO-29.

“Experimentation isn’t the problem, too much power is,” Stevens said. “It’s bad enough on SSB, worse with CW, and killer on constant duty cycle modes like FT8.” — Thanks to AMSAT News Service 



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