[Lowfer] Looking for 73 kHz band modes to try...

[Cliff Sojourner]

great info!  thanks, folks.  Cliff

On 2013-12-05 20:08, Charlie , W5COV wrote:
> Found this :
>
> **
> Solution Details : Dear Mr. Nieto,
>
> As I reported Timothy J. Lilley, the licensee of the station 
> transmitting the emission is responsible for determining that the 
> operation of the station complies with the rules.
>
> According to the technical paper and the audio file attached, we 
> conclude that ROS can not be viewed as Spread Spectrum and it would be 
> encompassed within the section 97.309 (RTTY and data emissions codes).
>
> FCC Committee will remain outside of any legal action you decide to take.
>
> Should you have any further questions, or need additional information, 
> please contact the ULS Customer Support Hotline at (877) 480-3201 
> (877) 480-3201, selecting option 2.
> Sincerely,
> Agent 3820
>
> **
> On 12/5/2013 8:38 PM, jrusgrove at comcast.net wrote:
>> It's ROS mode that's involved in the spread spectrum controversy. 
>> OPERA mode is simply on off keying.
>>
>> Jay W1VD  WD2XNS  WE2XGR/2  WG2XRS/2
>>
>>
>> ----- Original Message ----- From: "JD" <listread at lwca.org>
>> To: "Discussion of the Lowfer (US, European, &amp;UK) and MedFer 
>> bands" <lowfer at mailman.qth.net>
>> Sent: Thursday, December 05, 2013 8:06 PM
>> Subject: Re: [Lowfer] Looking for 73 kHz band modes to try...
>>
>>
>>>>> Opera is not legal to tx in the US, FCC thinks it is a 
>>>>> spread-spectrum mode.
>>
>> Actually, Cliff, that's what its own, er, inventor called it, way 
>> back when.
>> Perhaps they took his word for it.  It's not really SS, of course.  
>> It uses
>> no energy-spreading techniques; it's merely frequency agile.
>>
>> But it's still not legal below 50 MHz in the US amateur service for a 
>> much
>> more fundamental reason...the same reason WSPR and PSK31 and others 
>> *do not*
>> meet the published Part 97 requirements on HF, either!
>>
>> In 160m and all relevant segments of the HF bands through 12 meters 
>> where
>> RTTY and data are permitted by Sec. 97.305, Note 3 of 97.307(f) also
>> applies:  "Only a RTTY or data emission using a specified digital code
>> listed in §97.309(a) of this part may be transmitted. The symbol rate 
>> must
>> not exceed 300 bauds, or for frequency-shift keying, the frequency shift
>> between mark and space must not exceed 1 kHz."  (At 10m, it's Note 4
>> instead, which is exactly the same except for a 1200 baud symbol rate.)
>>
>> Well, obviously the baud limits and the maximum frequency shift are 
>> not the
>> problem.  But if you follow on to 97.309(a), you find that there are 
>> only
>> three coding methods specified for RTTY and data emissions...5-level 
>> Baudot,
>> AMTOR, and ASCII.  That's all!
>>
>> Unspecified codes _are_ permitted by Notes 5 and 6, but those notes 
>> apply
>> only within bands above 50 MHz.  Thus, OPERA and the other 
>> aforementioned
>> modes are legal up there, with a few restrictions.  And, Part 5 
>> licensees
>> are not under the requirements of 97.309(a) at all, so there's 
>> presently no
>> problem using any of these modes in the US at LF and VLF.
>>
>> (QRSS employs International Morse, the coding method explicitly 
>> defined for
>> CW in 97.3(c)(1) and permitted virtually everywhere in the ham bands by
>> 97.307(a).  Hellschreiber is an image mode, on which few specs are 
>> stated in
>> the Rules other than bandwidth limits, so no problem there either.)
>>
>> But assuming we do someday get 2200 and/or 630 meters in the amateur
>> service, one of two things will need to happen before it's legitimate 
>> to use
>> popular digital modes in those bands:  (1) there will need to be yet 
>> another
>> new slow mode that does, in fact, utilize one of the currently specified
>> codes; or else, (2) developers of this sort of software will need to get
>> together and agree on a nice, efficient varicode they can all get 
>> behind,
>> publish it, and then petition the FCC to include it in the specified 
>> codes
>> of 97.309(a).  I have no doubt most of us here would gladly support 
>> such a
>> petition.  Then some variant of each of these worthwhile digimodes 
>> would be
>> legitimate for American ham use in all bands.
>>
>> 73
>> John