I think that a lot of people are missing the point with ROS and Spread Spectrum here in the US.
The author defined it as Spread Spectrum, only changing it to FSK144 (or whatever) after being told that SS was not allowed below 1.25m in the US. The FCC rules don't mention bandwidth in relationship to SS, they don't say that it "must employ bandwidths that greatly exceed the bandwidth necessary to convey the intelligence", nor do they reference any Wikipedia/ARRL/RSGB/ITU or other organization's definition. They simply mention SS as not being allowed below 1.25m. So, you can say that it is only 2.2kHz in bandwidth, but if it is spread spectrum within that 2.2kHz of bandwidth, it is illegal in the US below 1.2m. It could be 500Hz in bandwidth, but if it uses SS, then it is illegal. Is this the way it should be? No. Does it impede innovation and development of new modes? Yes. However, the way the rule is written is what we have to follow. Don't like it? Then petition the FCC to modify part 97 to allow SS within a limited bandwidth (say 3 kHz). As Skip has pointed out, there is a way to do this without mentioning ROS (or CHIP64/128) or any other SS mode. Quote the definition and petition for a modification, possibly with a bandwidth restriction, possibly without. But, without changing the rule, the rest of the discussion is moot. Dave K3DCW On Jul 13, 2010, at 2:23 PM, [email protected] wrote: > Hi Alan, > > Why did you wait so long with contributing here? > Please explain. > > ++ In Feb of this year I quoted from the ARRL's Spread Spectrum Source book > page 5-2 ++ > > " Spread Spectrum Fundamentals " > > SS systems employ radio frequency bandwidths that greatly exceed the > bandwidth necessary > to convey the intelligence. > > Bandwidths for SS systems generally run from 10 to 100 times the information > rate. > > etc etc. > > I got shouted out of the Group by addressing the use of ROS in the US by the > experts on > SS. > > Dave K3DCW www.k3dcw.net
