Thank you for your opinion, but need to be told to "calm down" as I am not excited! The FCC rules are plain and the description of ROS by the author is frequency hopping, whether within a phone signal bandwidth or not, so that identifies it as spread spectrum. I am sure the FCC rules were intended to prevent overly wide signals on HF using spread spectrum and therefore they only permit spread spectrum above 222 Mhz, where there is plenty of room.

ROS is a really nice mode, but I will be using it only on 432 Mhz, in accordance with our FCC regulations. Others under FCC jurisdiction are welcome to use it at their own risk on HF.

The current FCC rules are also probably intended to allow FCC monitoring which is not possible with conventional spread spectrum, so I hope the rules can be changed for spread spectrum modes like ROS which can be copied by third parties, but until that happens, rules are rules, and we are legally obligated to abide by them.

73 - Skip KH6TY




kp4cb wrote:
Ok calm down, que no panda el cunico como decia el chapulin, this mode is legal.

Read this and you will know why is an article of the ARRL


http://www.arrl.org/FandES/field/regulations/techchar/Chip64.pdf




--- In digitalradio@yahoogroups.com, KH6TY <kh...@...> wrote:

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 <mailto:digitalradio%40yahoogroups.com>, Andy obrien <k3ukandy@> wrote:
<http://groups.yahoo.com/group/digitalradio/members;_ylc=X3oDMTJmbzY3MjhrBF9TAzk3MzU5NzE0BGdycElkAzE4NzExODMEZ3Jwc3BJZAMxNzA1MDYzMTA4BHNlYwN2dGwEc2xrA3ZtYnJzBHN0aW1lAzEyNjY1OTc1MzA-?o=6 <http://groups.yahoo.com/group/digitalradio/members;_ylc=X3oDMTJmbzY3MjhrBF9TAzk3MzU5NzE0BGdycElkAzE4NzExODMEZ3Jwc3BJZAMxNzA1MDYzMTA4BHNlYwN2dGwEc2xrA3ZtYnJzBHN0aW1lAzEyNjY1OTc1MzA-?o=6>>Joe,
N8FQ...

http://www.arrl.org/FandES/field/regulations/news/part97/d-305.html
<http://www.arrl.org/FandES/field/regulations/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




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