We can see it as we want, but if OLIVIA is legal, ROS is legal.
________________________________ De: KH6TY <kh...@comcast.net> Para: digitalradio@yahoogroups.com Enviado: vie,19 febrero, 2010 19:19 Asunto: Re: [digitalradio] Re: ROS, legal in USA? All, If we accept the fact that a SSB transmitter with sufficient carrier suppression simply generates an RF carrier equal to the suppressed carrier frequency plus the tone frequency (USB), then frequency hopping is frequency hopping (spread spectrum), regardless of how the carriers are generated. That is really too bad for US hams as all morning I have been receiving alerts and printouts from many stations on 14.080 - many times when the ROS signal can hardly be heard above the noise. I'm afraid that Andy's concerns are real, and unless the FCC clarifies otherwise, ROS is currently illegal in the US in my personal opinion and interpretation of the FCC rules. However, it looks like a worthwhile mode to test on UHF (432 MHz) where SS "is" allowed and we will be doing that during our daily digital experiments every morning on 432.090 SSB. The Doppler shift, multipath distortion, and "fast flutter", as well as QSB often as deep as 15 dB, often make even S3 phone signals unintelligible. We have been also been testing extensively with DominoEx 4 on FM (DominoEX does not survive Doppler shift well on SSB) and Olivia 16-500 and 4-500 on both FM and SSB, often with better copy than with SSB phone, and especially so when signals are near the noise threshold. The path length is 200 miles, so signals are usually near the noise threshold during these winter months where there is no propagation enhancement. I'll post the results of our tests on 432 MHz here during the next two weeks as we compare ROS to Olivia. So far, plain old CW can be copied when even Olivia cannot, but the CW "note" is very raspy sounding, much like it is during aroura communication. It would help a lot if it were possible to select alternate soundcards and many of us on UHF and VHF are using a second soundcard for digital operations. 73 - Skip KH6TY nietorosdj wrote: > >One comment: It is not the same a Spread Spectrum Transceiver (like military >radios) that to send digital data into an audio channel on standard SSB >transceiver. They are different things. So, when we read Spread Spectrum is >not legal, first we must know what we are reading. > >--- In digitalradio@ yahoogroups. com, Andy obrien <k3uka...@.. .> wrote: >> >> <http://groups. yahoo.com/ group/digitalrad io/members; _ylc=X3oDMTJmbzY >> 3MjhrBF9TAzk3MzU 5NzE0BGdycElkAzE 4NzExODMEZ3Jwc3B JZAMxNzA1MDYzMTA >> 4BHNlYwN2dGwEc2x rA3ZtYnJzBHN0aW1 lAzEyNjY1OTc1MzA -?o=6>Joe, >> N8FQ... >> >> http://www.arrl. org/FandES/ field/regulation s/news/part97/ d-305.html >> >> Describes Spread Spectrum as not permitted on HF. Is there another part of >> part 97 I am missing ? >> >> Andy K3UK >> > >
