[RTTY] RM-11708 FAQ posted

[Kai]

Currently, and applying broadly to the FCC term "RTTY",  97.307(f)  - "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. "
That means two-tone FSK RTTY at up to 300 baud and up to 1000 Hz shift is 
permitted, and has a bandwidth of 1500 Hz* (not 500 Hz).  Digital emissions that 
do are not subject to the "or for frequency-shift keying, the frequency shift 
between mark and space must not exceed 1 kHz" restriction of 97.307(f) are 
subject ONLY to the 300 baud restriction (there are several ham digital 
non-voice modulations in use with up to about 2400 Hz BW today: G-TOR, PacTor, 
Clover are specifically listed by the FCC; there are more). If one choses to, 
and has a good reason to, one could legally occupy, as I stated, in the 100's of 
kHz.

So many of us see and understand that the technology has outpaced the out dated 
97.307(f), since it restricts the bandwidth of two-tone FSK RTTY ONLY, and not 
any other digital modulation. But the 300 baud limit can render many other 
digital modulations very spectrum inefficient (but not illegal) without limiting 
their bandwidth.

RM 11708 seeks to replace that 97.307(f) phrase with "The authorized bandwidth 
is 2.8 kHz."

*See US CFR 2.202 for bandwidth calculation of two tone FSK RTTY:   BW = 
BaudRate + 1.2Shift = 300+1.2(1000) = 1500 Hz.

-Kai, KE4PT


On 2/27/2014 11:25 AM, Joe Subich, W4TV wrote:
>
> Were we to see some lid or lids fire up with 300 KHz wide signals on
> 10 meters - or 200 KHz wide signals on 160 meters - ARRL and the FCC
> would quickly scramble to impose a bandwidth limit.  2.8 KHz in the
> spectrum traditionally reserved for bandwidths 500 Hz and less is just
> as bad as 200 or 300 KHz- as the punch line of the old joke goes:
> "Young Lady, we have already determined what you are - now we're only
> haggling over price."
>
> And before you try to argue again that 500 Hz is not the de facto
> standard, read *the Commission's *own words* at footnote 89, page 12 of
> http://hraunfoss.fcc.gov/edocs_public/attachmatch/FCC-06-149A1.pdf in
> which they forcefully *rejected* ARRL's request that *image* modes not
> be restricted to 500 Hz bandwidth in the "data" allocations.  Note:
> even *analog* image modes are permitted in the "data" allocations as
> long as their bandwidth is less that 500 Hz.
>
> As far back as 2006 the Commission made it absolutely clear to ARRL
> what they would accept and what they would not accept.  ARRL's Board of
> Directors, CEO and Counsel are quite simply incompetent and dishonest
> in their handling of this matter.  Had they simply requested that RTTY
> and Data modes as defined in 97.3(c)(7) and 97.3(c)(2) be added to the
> emission types where voice and image emission re already permitted and
> the 500 Hz limit currently in 97.3(2)(2) be extended to all data modes
> below 30 MHz where voice and image are *not* currently permitted, this
> matter would be completely non-controversial.  The rules currently limit
> non-voice modes to 2.8 KHz (single channel) or 6 KHz (multiplexed) in
> the "voice/image" segments - there would be no need to impose a special
> limitation.
>
> The Commission would have gladly made the *minor* changes - which would
> prevent the doomsday scenario both you and the ARRL are using to panic
> amateurs to support a *bad* proposal which will ultimately destroy narrow band 
> modes.  If you don't believe that allowing 2.8 KHz data will
> destroy the narrow band modes, just wait and see how quickly ALE, STANAG
> and other 2.8 KHz "data" modes carrying primarily digital voice start to
> pour into the "data allocations" once wideband modes are "blessed" by
> this proposal - their advocates are salivating on the sidelines right
> now.
>
> 73,
>
>    ... Joe, W4TV
>
>
> On 2/27/2014 10:53 AM, Kai wrote:
>> Ron,
>> Answer:
>> Wide bandwidths are not prohibited under today's rules. Bandwidths of up
>> to 200 kHz depending on the MF-HF ham band (300 kHz at 10m band) are
>> *permitted* today in the digital sections of our bands. Under RM-11708
>> there would be a limit of 2.8 kHz, a massive DECREASE in the allowed BW
>> for Data/Digital modes.
>>
>> Band plans like we have already, and courteous operation (like most of
>> the RTTY community) are very good ideas.
>>
>> 73
>> Kai, KE4PT
>>
>>
>> On 2/27/2014 1:53 AM, Ron Kolarik wrote:
>>> Yup, trust us. This is what one question/answer should look like
>>>
>>> Q. Did ARRL evaluate the potential for interference to RTTY, CW and
>>> narrow bandwidth data modes that could result from an increase in
>>> wider-bandwidth data stations? A. Yes. we asked K5RAV and the rest of
>>> the ad hoc digital committee and they thought it was
>>> okey dokey fine. We'll put a bandplan in after we get enough
>>> complaints, we want a bandplan not regulation, it's easier to ignore a
>>> bandplan if no one can identify a station or content and
>>> no pesky regulations that carry the weight of law.
>>>
>>> The rest isn't much better and the cynic in me says I should provide
>>> new answers
>>> to all the questions and send them to Sumner but he has a history of
>>> ignoring input.
>>>
>>> Ron K0IDT
>>>
>>>
>>>
>>> ----- Original Message ----- From: "Mark" <n2qt at yahoo.com>
>>> To: "Ron Kolarik" <rkolarik at neb.rr.com>
>>> Cc: "RTTY" <rtty at contesting.com>
>>> Sent: Wednesday, February 26, 2014 10:53 AM
>>> Subject: Re: [RTTY] RM-11708 FAQ posted
>>>
>>>
>>> Basically, a "trust us". And if it goes all wrong, well something can
>>> be done eventually...
>>>
>>> Mark. N2QT
>>>
>>>
>>> _______________________________________________
>