Here’s N9NB’s response to N8OHU’s points.
73, Jim N7US
From: Ted [mailto:tsrwvcomm@aol.com]
Sent: August 14, 2016 10:12
Sent from smartphone, please excuse typos
On Aug 14, 2016, at 10:55 AM, Ted <mailto:tsrwvcomm@aol.com> wrote:
Hi Matthew: thanks for sending me your note.
I am not a part of the RTTY email list. So, I would ask you to please forward
my note as a rebuttal to your comments. I will also send this to a few people
who are perhaps on that RTTY alias, in case you don't care to forward my note.
I am happy to reply to Mathew Pitts' comments, and hope you all will read
carefully the NPRM issued by the FCC this July 28, 2016. And please spread the
word. This is not fear mongering, as I have too many things to do in my day job
to spend time on anything that is not real. I am trying to get people to read
the NPRM and realize what is happening – and it's sad for me to see how hard it
is to get CW/RTTY enthusiasts to realize that they are false to assume the ARRL
and FCC would preserve CW or RTTY. They now have to take serious action if they
care about preserving their operating bands.
Understanding this and the history of the digital aggression goals of ARRL,
WINLINK, and the boating community is vital to realize the ramifications of the
July 28 2016 NPRM by the FCC. The NPRM 11708 of July 28 2016 is about to become
law and is what the FCC intends to do if there is not a vocal outcry.
In particular, please read Paragraphs 9 through 12 of the FCC's NPRM of July
28,2016 super carefully! That’s where it is clear that the DATA/RTTY HF
subbands, which include ALL CW and RTTY frequencies, from the lowest edge of
the HF band up until the Voice/Image subbands, will be subjected to unlimited
bandwidth new data signals. That is, the FCC is proposing to authorize
UNLIMITED BANDWIDTH, and UNLIMITED DATA RATE signals in the ENTIRE Data/RTTY HF
subbands from the lowest edge up to the SSB/Voice/IMAGE subbands. All of the CW
and RTTY frequencies are impacted in that sub band – that’s where CW and RTTY
operate – that should be clear to anyone reading the NPRM.
This NPRM is a rule, with the force of law, about to be passed by the FCC. It's
already gone much farther than RM 11306 did when the ARRL tried this same
proposal at the FCC in 2005 to put this wideband data in the SSB/Phone/Image
band – the ARRL pulled it because the SSB operators were well organized and
vocal. But now they have gotten it through the FCC in the CW/RTTY subbands ---
it never went that far before, because SSB hams shouted it down at the
ARRL............sadly CW/RTTY operators have not been successful and have had
huge apathy and skepticism about the threat, and now this is about to become
law unless there is a MAJOR outcry and comments at both the FCC and ARRL to
stop the interference in the lowest 100 kHz.).
Please, please educate yourself by reading about RM 11306 on the web. It was a
ferocious battle in 2005-2007. The ARRL withdrew it in 2007, finally. They then
retooled it in 2013 as RM 11708, and have it about ready to get into law –
UNLESS people respond mightily to ARRL officials and the FCC during this
2-month comment period. this is not fear mongering, I assure you. It's trying
to get people awake and aware of the pending law in the FCC publication.
Without strong consideration and response, ham radio in the US will be subject
to this rule making, and it's going to be very bad for CW/RTTY, just like the
SSB ops saw and successfully fought off in RM 11306.
For history, see RM 11306 on the web. So many thousands of posts rejected RM
11306, an ARRL board member resigned in disgust, here is just one simple sample
assessment, when the ARRL proposed this identical proposal 10 years ago, except
in the phone sub bands, (Now they are getting it into the Data/RTTY subbands,
which by definition are where CW and narrowband modes operate):
http://www.eham.net/articles/13018
Here are specific answers to some of your questions or doubts about the gravity
of RM 11708 by the FCC:
Yes, this impacts all CW and RTTY on HF, because the NPRM specifies all HF
“Data/RTTY” subbands. That is the subband where CW and RTTY and narrowband JT65
and PSK 31 operate.
Yes, the FCC is proposing UNLIMITED bandwidth. Even if the FCC accepted ARRL’s
2.8 kHz bandwidth limit, the problem STILL negatively impacts CW and RTTY
signals, since Pactor 4 and other HF modems will be allowed in ANY CW/RTTY
frequency, and digitized voice of up to 2.8 kHz bandwidth will also be allowed
on ANY CW /RTTY frequency. This would cause wider band SSB-like bandwidth
signals to mix and overtake CW/RTTY narrowband signals. Note that CW has only
200 Hz max bandwidth, RTTY has 500 Hz max bandwidth. These narrowband signals
cannot be used when they are clobbered by 2.8 kHz wide band signals. That is
why the FCC never allowed SSB to operate on top of the CW/RTTY signals. We must
keep this segregation by bandwidth to assure CW and RTTY can operate without
wideband interference. That is why I and others are advocating that the NPRM be
MODIFIED to limit the emission bandwidth to 200 Hz in the lowest 50 kHz of each
HF subband, and why a limit of 500 Hz should be enforced for the lowest 100 kHz
of each subband. That would assure that CW and RTTY would not be subjected to
wider band interference, while still allowing wider band data to exist above
100 kHz above the lowest HF edges.
Regarding Pactor and its problems, that is, what we will be subjected to if the
ARRL’s 2.8 kHz bandwidth is eventually accepted at the FCC (right now, that
does not look likely – the FCC wants to open the bandwidth to be much greater –
unlimited) PACTOR in general (I do not know the specifics of PACTOR 4) uses run
length encoding and decoding a technique in which common words and
strings of two or more letters (e.g., sh, ing, in, on, the, etc.) are replaced
with a "token." In addition, the resulting message is then compressed
(apparently PACTOR 4 adds the ability to use an encrypted "key" for the
commercial version).
However, the developers of PACTOR do not release details of either the
compression algorithm or the substitution table for PACTOR 2 - 4, so it's not
really public, and its unintelligible unless you buy the $1500 modem. and there
is no CW ID. Yet it's being used today in ham radio under the guise of being
published. It’s a grey issue.
When you read the FCC NPRM Paragraph 10, they mention 97.309(a) as being the
only codes allowable on HF/MF, but the problem is §97.309 (a) contains several
parts - it specifies ITA 2, AMTOR (SITOR)
and ASCII data formats ("Codes") but also - in §97.309 (a)(4) - lists several
permitted *transmission methods* (or "encoding methods") "whose technical
characteristics have been documented publicly" including PACTOR. But that’s not
really what's happening today.
The issue is that the only the original PACTOR was *publicly documented* - the
PACTOR 2 - 4 encoding systems are **NOT** publicly documented! Yet Pactor 3 is
operating today. People cannot stop or identify offending transmissions that
QRM them with Pactor 3. Will be so much worse with Pactor 4 and future data
signals!
Another major real problem is in §97.309 (b) which permits "undocumented codes"
under certain circumstances. The loopholes in §97.309 (b) are big enough to
drive a bus through. Has been the cause of QRM already for years with automated
data.
All of this will become so much worse if NPRM is legalized, and the FCC is not
dealing with these issues and are ignoring it, as you can see in NPRM paragraph
10, where it simply assumes all hams will use only enough bandwidth as they
need. Yet the FCC contradicts itself and says that wideband experimentation
should be supported, of arbitrary large bandwidth, so there is a huge disaster
waiting to happen if the NPRM is passed as is ---- the existing problems with
Pactor will immediately erupt into a huge mess and no regulation on the TTY
subbands! right now, the FCC is leaning towards no bandwidth protection and no
bandwidth limit for the lowest 100 kHz of each HF band for CW/RTTY to keep all
emissions below 200 or 500 Hz. You allow wider transmissions than this, e.g.
unlimited bandwidths as proposed by the FCC, or 2.8 kHz bandwidths as
originally proposed by the ARRL, and the entire CW/RTTY lower portion of HF
becomes swallowed up in wider bandwidth data signals, either PACTOR or wider
with digitized voice, etc. over time. that is what is at stake. I hope this
makes sense! {Please, please get active and spread the word, if you care about
CW or RTTY.
Thus, Matthew's desire to minimize the impact of the FCC's proposal is not
accurate. Also, Canada has a tiny fraction of hams as the US and propagation
from VE often goes over the US on high bands- It's a red herring. This is a
real threat to all of RTTY and CW and requires immediate action and thoughtful
comments to the FCC and ARRL officials.
73 ted n9nb
Sent from smartphone, please excuse typos
On Aug 14, 2016, at 10:34 AM, Matthew Pitts <mailto:n8ohu@yahoo.com> wrote:
Some major flaws that I see in his argument are:
1: Digital voice is classified as "Phone" hence not permitted in the RTTY/data
segment to begin with; that won't change even if the FCC bandwidth proposal is
enacted as written.
2: Data compression is not encryption, and Winlink doesn't even use the Pactor
data compression anyway; they use the same one that is used in the F6FBB Packet
BBS. Also, the FEC ID capabilities for all versions of Pactor are identical, so
any software that can decode Pactor 1 can be used to ID an interfering station.
3: Despite what he's claiming, there is absolutely no interest in
implementation of such things, even if some tiny fraction of users might want
to see it happen.
4: As I said before, claims of a massive increase in the number of automatic
stations or wide bandwidth digital voice stations swamping the RTTY/Data bands
are nothing more than FUD.
Also, a 500 Hz bandwidth limit would do little to reduce interference when
Canada has a 6 kHz bandwidth limit.
Matthew Pitts
N8OHU
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