ROS is MFSK16 with frequency hopping so it is SS per the FCC definition as the bandwidth is expanded. However, the FCC never fined anyone during the period when Hellscreiber was used illegally so I doubt that they would do so with ROS.
What ROS users should do is email their ARRL representative and have them petition the FCC to change the rules. One solution is to eliminate the emission designators and change the RTTY/data segment of each HF band to 0-500 Hz wide emissions and the phone/image of each HF band to 0-8 kHz wide emissions with 0-20 kHz above 29 MHz. 73, John KD6OZH ----- Original Message ----- From: J. Moen To: [email protected] Sent: Saturday, February 20, 2010 20:35 UTC Subject: Re: [digitalradio] Re: ROS, legal in USA? Sticking with the USA/FCC-centric discussion, I agree with Alan KM4BA, when he wrote: "If the radio stays on a single frequency in SSB mode the new mode does not meet the definition of spread spectrum that is restricted in HF. Many advanced digital protocols manage the spectrum in the SSB bandwidth to achieve performance. But since the implied carrier frequency is not moving, it's not spread spectrum in the classic sense." It does not matter what the ROS authors write to describe it. It isn't illegal in the USA because they call it SS, all that matters is how a competent engineer would technically describe it. FCC rules do not say it is illegal to use a mode that describes itself as SS on HF, they say that SS is not allowed on the HF bands. And saying ROS is SS doesn't make that true. I also agree with Andy G4JNT's point that Amateurs should be allowed to experiment. Historically in the USA, the FCC has indeed allowed experimentation, then come along with appropriate rules once the new technology is better understood. I think all this legal discussion is trying to make, as they say, a mountain out of a molehill. Jim - K6JM
