For folks involved in RM-11708, here is a interesting email thread from the
Central Texas DX and Contest Club that contains thoughts from the CW side of
things. It's encouraging to see that other key individuals in our hobby
have picked up on RM-11708 issues and are expressing their concerns.
Please continue with all of your efforts to get the word out.
Thanks,
Terry
---------- Forwarded message ----------
From: Ted Rappaport <tedrappaport@verizon.net>
Date: Sun, Mar 23, 2014 at 12:38 PM
Subject: Regarding RM-11708 -=-= this is really bad!
To: CTDXCC List List <ctdxcc@kkn.net>, (AB5K note: rest of email list
intentionally deleted..)
Dear Colleagues:
Heavens knows that we are all very busy people, but on rare occasion,
something comes up that is important enough to require us to take the
unusual step of putting down whatever were are working on, and to get deeply
involved in an effort to help our community, with the hope of helping years
into the future.
Repelling RM 11708 is one of those rare occasions where I am compelled to
take time out and give this my full attention.
I must tell you I worry about the massive number of emails that might result
from this note I am sending, and I am being transparent in the "to" box, so
I would simply ask that we NOT respond-- please let's not clutter up each
other's inbox..don't even thank me or blast me, whether you agree with me or
not......all I ask of you is to please consider this dialogue between many
active hams, below, many who you may know, and then decide what you want to
do about this rulemaking on your own, or in your own circle of influence.
I promise I won't spam you again. All I ask is that you please take this
under advisement, and do with this information whatever you care to do with
it. My hope is you take action of some kind, whether you agree with me or
not. We need to be involved, because as written, RM-11708 will be a disaster
in my technical opinion. Key leaders and key emails are given the dialogue
below, if you want to follow up on your own. Please take a quick read, and
see for yourself.
I had heard about this rule making 11708 in one of my favorite DX club
reflectors a few weeks ago, with heated debate and the fear that the "death
of CW" was coming.
I did not pay any attention to the banter, because I believed that all was
surely well, that the ARRL knew better than a few fearful hams, and that a
few of my fellow human beings were being reluctant to change, etc. Plus, I
was way too busy at work to even bother with this silliness.
I thought for sure that the ARRL would properly and thoughtfully promote a
new set of digital modes-- after all, multilevel signaling is the key to
WiFi and 4G LTE cellular-- and it needs a place to grow in our hobby, as do
all futuristic signaling methods. At the same time, I was confident that the
ARRL would similarly protect CW, a mode of communication that launched the
wireless revolution and was key to my ability to stay in the hobby even when
I didn't have a tower or an amplifier over more than 35 years. We all know
that CW is the only mode with such a small bandwidth that best facilitates
long distance communication, low power communication or QRP operation, and
allows a new ham to deploy a very economical station (barefoot with wire
antennas, or even put into Altoids boxes), and I was sure that the ARRL was
cognizant that DXpeditions to faraway places rely on CW for most of their
QSOs because of the narrowband nature, and the good filtering that we can
use. I was quite sure that when I went to look at the ARRL FAQ page at
sunrise this morning, there would be good rationale and a fair technical
approach to introducing new digital modes that are becoming increasingly
popular and important to our hobby.
But this morning, I spent a couple of hours digging into this, and was quite
horrified.
Hence, this very rare email to all of my Hamvention VIP friends of Janeen
Hire, and a few others.
You are some of the movers and shakers of the hobby, and I believe that your
involvement and activism is needed (let the dialogue below inform you to
whatever degree you care to. No need to respond to this, please).
Suffice it to say that my couple of hours reviewing the open literature on
this proposed rulemaking gives me great concern. Apparently I am not alone,
but the ham community needs to be vocal.
It appears that the rulemaking wants to introduce a digital modulation that
is 5 to 7 times the bandwidth of today's CW signals, and wants to lawfully
allow any ham to plop those new digital signals anywhere they want to in the
CW-only portion of the band. Even if voluntary band planning is ever
implemented, the fact is that this proposed rulemaking threatens to remove
the lawfully protected CW-only status of the CW portion of the band.
The new proposal will introduce bandwidth hogs right into the protected
spectrum of where narrowband CW transmissions (where each CW transmission
has a 400 - 500 Hz bandwidth - that is a liberal estimate) have historically
been protected from the wider bandwidth SSB signals (say 2.4 - 2.8 kHz
bandwidth). The sad fact is that these new, exciting digital signals that
are being proposed for introduction into the protected CW bands have
essentially the same bandwidth as SSB signals, yet the proposal puts these
new SSB-like signals lawfully into the CW band. Thus, this RM proposal is
essentially a proposal to remove the long-lived legal protection of CW.
CW has coexisted with RTTY (RTTY can have an RF Bandwidth of slightly less
or more than one CW signal -- 250 -600 Hz, as can be seen here:
http://elecraft.365791.n2.nabble.com/K3-RTTY-bandwidth-already-too-narrow-td
<http://elecraft.365791.n2.nabble.com/K3-RTTY-bandwidth-already-too-narrow-t
d%0A7571756.html>
7571756.html and here: http://en.wikipedia.org/wiki/Radioteletype
Avid CW operators and RTTY/PSK31 operators have perceived more interference
from the current digital modes, simply because there has been a much greater
increase in hams using these modes, and while everyone seems to do a nice
job obeying the agreement of voluntary segregation of the CW bands, the
numbers are dramatically increasing for digital operation. That's a good
thing. However, it is critical to know that RTTY has the bandwidth of about
one CW signal. And PSK31 actually has a bandwidth of about 1/3 of a CW
signal. Thus, the beauty of the protected bands and the narrow bandwidth of
RTTY and PSK31 allow all of us to operate in harmonious fashion.
See:
http://www.arrl.org/psk31-has-rtty-s-replacement-arrived and
http://en.wikipedia.org/wiki/PSK31
The horror of this new proposed rulemaking 11708 is that the ARRL is
backing a plan to now introduce SSB-like signals (signals that have
bandwidths of 5 to 7 independent CW signals) into the protected CW bands.
Given the rapid growth of digital users in our hobby (a good thing),
compounded with a new signal that hogs 7 X the bandwidth of today's RTTY
Signal, we are in deep trouble-- In fact, it made me wonder how the ARRL
could ever propose this in the first place without such careful thought.
Further work, described below, shows that the ARRL arguments are in fact
technically flawed and misleading.
I could easily do analysis (so could many of you) showing the huge loss of
CW user capacity (e.g. the number of CW users per band will be drastically
shrunk due to the massive increase in interference from the new digital
signals) in the face of an increasing number of new 2.8 kHz digital
signaling modes in the protected CW band. Very rapid deterioration will
ensue unless there are truly forbidden frequencies, by law, that protect CW
and the other narrowband digital modes such as RTTY and PSK31. This proposed
rulemaking will not provide the continued protection, by FCC law, and if it
is passed, these new digital signals would quickly overtake the CW spectrum,
just as if SSB were allowed to operate in the protected CW band......We must
realize that this new digital modulation is just like SSB in terms of
bandwidth occupancy and interference power spectral density. The new
rulemaking essentially is akin to allowing digital equivalents of SSB
signals to occupy the CW band freely.
Due to the fundamentals of Signal to Noise Ratio, and the Power spectral
density of a SSB signal and thse new 2.8 KHz digital signal, as compared to
a CW signal, it is ALWAYS easier to operate using a wider bandwidth signal
in the face of an narrow band interferers (e.g. it is easy to copy a
detectable SSB signal while a cw transmission occurs, because the narrowband
CW signal occupies a much smaller percentage of the SSB spectrum, and can be
nulled out or ignored without a great change in the Signal to Interference
(SINR) ratio of the received SSB signal. This is why the FCC has always
allowed CW to operate in the SSB band. It is because energy in a received
signal is spread out over 2. 4 or 2.8 kHz in a SSB signal, and thus the area
under the curve is much greater for the wider band signal. A simple notch
filter can remove the single tone CW signal (or our brain can do it), and
given that we are already receiving the SSB signal above a noise threshold,
we can tolerate a narrowband interferer, and SSB works fine. Hence today's
rules that allow CW to operate in the SSB bands.
However, it is MUCH HARDER to copy a narrowband signal in the face of wider
band interference source (that's why the CW bands have always been
protected). The narrow band nature of CW is sensitive to any energy that
falls within its narrowband spectrum, and a wider band interferer will have
some portion of its energy falling into the CW channel of interest. The CW
signal cannot notch out the wideband energy in its own channel without also
notching out its own signal -- thus, the interference effect is MUCH GREATER
when a wideband signal spreads its energy across a narrowband signal (anyone
experience the effect of hearing the woodpecker over the horizon radar, or
when you try and maintain a CW QSO and a broad pile up erupts around your
frequency? ) The broad interferer wipes out the narrowband CW signal. What's
worse is that the wider band interferer also simultaneously interferes with
MANY CW QSOs at the same time. Yet, the ARRL proposal is PROPOSING TO
ALLOW WIDEBAND INTERFERENCE on the protected CW band! This cannot be
allowed, or else CW will be overtaken very abruptly. THE FCC LAW THAT
PROTECTS CW, AND CW-LIKE BANDWIDTH SIGNALS SUCH AS RTTY AND PSK31,MUST BE
PROTECTED IF WE CARE TO MAINTAIN THE VIRTUES OF CW.
Why the ARRL did not propose the new digital signals to occupy the SSB
bands, where the bandwidths are matched 1:1, is beyond me (actually, I
understand the nuances of the FCC law, and can understand why the ARRL might
have been a bit hesitant, but this could have and should have been argued as
a one for one bandwidth, and one for one user swap in the SSB spectrum. In
fact, I am relatively sure it would be looked upon favorably by the FCC in
the face of new digital VoIP and multi-level keying for voice communications
today-- remember when the cellular world went from Analog FM in first
generation cellphones to 2nd Generation TDMA IS-54, IS-95 in the same 30 kHz
channel bandwidths? This easily could be proposed to the FCC to get a quick
win on allowing the new digital modes to share the SSB spectrum -- and that
is what the ARRL should do as it has much less impact on a user basis.
I cannot hide my deep disappointment at the ARRL, when I viewed their FAQ on
this rulemaking and their rationale.
http://www.arrl.org/rm-11708-faq
Below you will see my thoughts and comments. I hope you will get involved.
Thanks for listening.
73, ted n9nb
-----Original Message-----
From: Tim Duffy [mailto:k3lr@k3lr.com]
Sent: Sunday, March 23, 2014 11:26 AM
To: 'Ted Rappaport'
Subject: RE: regarding RM-11708 -=-= this is really bad!
HI Ted!
SO good to hear from you!
PLEASE send your comments to K5UR (SVP at ARRL), Ward Silver, N0AX (lots of
influence at ARRL) and Dave Patton, NN1N (really runs HQ activities and a
SMART contest guy). AND also to Kay Craigie, ARRL President and Fellow of
RCA.
EMAIL:
K5UR@arrl.org
hwardsil@gmail.com
nn1n@arrl.org
n3kn@arrl.org
I totally appreciate your expert opinion to SHUT this down!
Hope you will make it to CTU and Hamvention.
I have had dinner twice with Julie in the past - GREAT GUY!
73!
Tim
-----Original Message-----
From: Ted Rappaport [mailto:tedrappaport@verizon.net]
Sent: Sunday, March 23, 2014 10:31 AM
To: (AB5K note: more emails deleted)
Subject: RE: regarding RM-11708 -=-= this is really bad!
I think all of you are experts and carry much weight. I copied my comments
to Dave Sumner when I submitted my comments to the League:
HF-Digital-Bandplanning@ARRL.org
I think all of you should ring in here with the ARRL and any ARRL board
members that you know (is W3LPL on the board? Maybe Tim K3LR?). I am copying
Tim K3LR and Tom N9NC, as they would also likely have some good technical
insights, and I suspect would also see the potential detriment to CW if the
rule making isn't readjusted to deal with this. You all know that I am the
first one to sign up and cheer for new technologies and modes, but this
approach is flawed, not just on a financial/long ;. fa
I think the league has really got it wrong, and has really underestimated
the importance of "peanut whistles" and low cost approaches that CW allows
in the hobby, not to mention the sunk investments and enjoyment of old
timers like us who support the hobby with contest stations, etc. It saddens
me that the ARRL, our lobbying arm, has arbitrarily attacked one old FCC
rule (symbol duration) and has arbitrarily ignored another old rule (voice
is phone). See their FAQ page:
http://www.arrl.org/rm-11708-faq
The ARRL has really stubbed their toe, I believe, and some of their
responses on the FAQ are quite troubling to me as an engineering expert,
because their arguments appear to be a slimy way to get something passed,
while their arguments are a smoke screen and not an accurate technical
approach. While the ARRL claims to be fighting against an obsolete term
(symbol rate), that is very far from the truth. They claim that they cannot
consider putting these 2.6 kHz digital modes in the phone band because
"voice is phone" in the FCC rules, and thus they don't want to touch that,
yet that is much more obsolete and much older than the "symbol rate" they
claim to be "fixing"....
In fact, virtually nothing today in voice is really "phone" in the real
world-- virtually all voice is today's modern digital world (skype,
cellphone calls, cordless phones) are actual digital transmissions just like
the ones they want to add in this proposed rulemaking. And, in the modern,
real world, any and all digital modes have "symbol rates" -- this is in
modern use. Yet, the ARRL argues it wants to eliminate "symbol rates"
because it is old. Nothing could be more wrong! Note that everything in
modern communications uses symbol rate, the very term they want to remove!
All licensed spectrum, cellphones, satellite, all must have a symbol rate
specified for interoperability and interference mitigation/planning/proper
reuse. Thus, the ARRL is really being quite arbitrary, and in fact
disingenuous, in their approach to this, and while I understand their
rationale to view these digital modes as an extension of RTTY, their logic
lacks the technical basis they claim on their FAQ page -- this looks like a
lawyer wrote it in a blatant attempt to reduce the CW allocation with a new
keying/modulation standard that is 5 to 7 times the bandwidth of a single
CW user. One single digital user will clobber 5 or 7 closely spaced CW
signals in a contest or dxpedition pile up. What a horrible situation! Yet
the arguments the ARRL uses are not steeped in technical fact. "symbol rate
is NOT old", yet "voice is phone - that IS old". Yet, they make an argument
that will swamp incumbent CW users by a factor of 5 to 7 in bandwith - they
will wipe out 5 to 7 CW conversations with one new digital user!
Unbelievable.
em mke ay
I completely forgot to mention DXpeditions and contests in my comments,
those are other good points and I wish I would have thought of that earlier.
Maybe all of you can reply with other good technical arguments as to why the
proposed rulemaking is really harmful. I noticed in a Thursday night sprint
a few weeks ago there were RTTY operators at 7.036 and they wiped out
several Khz. Imagine if you have these broadband digital modes all over CW
-- each digital mode will be like a SSB signal, right there in the CW bands.
It is a DISASTER.
I spent the day with Julius Knapp (we call him Julie) last year, and will
see him again in a month. I will give him an earful, but you can see
firsthand why we need to protect CW and the spectrum in general (on this
video, I put in a plug for ham radio in emergencies - this was part of a
forum that the FCC held at the Brooklyn law school after hurricane sandy....
http://www.youtube.com/watch?v=u5tZNpc4FtE (this is why I get the big
bucks...I can take 10 minutes to say what someone else could say in 10
seconds :-)
Julie will hopefully be on hand at our big summit:
www.Brooklyn5gsummit.com
73
ted
-----Original Message-----
From: Jim George [mailto:n3bb@mindspring.com]
Sent: Sunday, March 23, 2014 8:38 AM
To: (AB5K note: More emails deleted)
Cc: Ted Rappaport
Subject: Fwd: regarding RM-11708
Ted, I am taking the opportunity to forward your comments to the local lunch
gang here. Hope you don't mind. You carry weight based on your academic and
professional credentials. Tom, N5TW, is an expert on advanced digital modes
as well as practical aspects of digital traffic handling on the bands. He
has commented on the proposal, with detailed knowledge of the technology and
definition of "symbol rates." But the main reason I am taking this
opportunity is to thank you for your recommendations.
Currently, as I understand it, the present very-narrow traffic/email digital
protocols are limited to a defined small band segment somewhere in the area
100 KHz above the bottom of the CW bands. Clearly, I think it would be a
isaster to allow 2.8 KHz digital signals all over the CW and RTTY bands. It
would set a war in motion, reminiscent of the original SSB transition in the
old AM phone bands. In that case, clearly the survival of the better
technology took place over a bitter decade. In the case of RTTY versus
unlimited new wide digital formats, we would have unbridled anger.
It could split the ARRL into pieces and virtually destroy the League as we
know it. The same could be said if CW is threatened by unlimited digital
modes.
As an ARRL Life Member and an active ham for 56 years, this hobby has been a
key element of my life. Innovation is necessary and desired, but tradition
must be valued as well.
RTTY is a wide digital protocol, and clearly disrupts the heck out of CW
when they compete. Fundamentally, from my experience, CW loses out to any
digital protocol when they occupy the same frequency. Should there be
separate segments, for example, RTTY, Packet, SJPT stuff, Pactor, and CW?
No, clearly that gets into impossible complexity rather quickly. Should we
limit the bandwidth of these new innovations and force them to be able to
exist in defined bandwidths? Is that practical given the nature of so many
international interests in the ITU and UN? Should we simply let them all
exist and fight it out like the original transition from AM to SSB?
Survival of the fittest? "Frequency fights forever?" There must be a better
way.
I'd say that CW needs to be protected. And that's not just because it's my
favorite (and almost only) mode. It's the origin of amateur radio. Perhaps,
at some point, CW will become limited to a very small frequent segment since
only a few operators use it. That might exist at some time, although three
of the most compelling aspects and "killer apps" of ham radio are QRP,
contests, and DX-peditions. In any case, I'd support CW-only sub-band
segments of some size.
Jim N3BB
>From: "Ted Rappaport" <tedrappaport@verizon.net>
>To: <mailto:HF-Digital-Bandplanning@ARRL.org>
<HF-Digital-Bandplanning@ARRL.org>
>Subject: regarding RM-11708
>Date: Sun, 23 Mar 2014 07:55:44 -0400
>
>Dear ARRL:
>
>As a life member, and long time electrical engineering professor in
>the wireless communications field, I appreciate and applaud ARRLs
>efforts to continue the growth and exploration of new modes of
>communication in our precious spectrum allocation.
>
>However, as one who believes that it is vital to preserve CW as the
>best low-power means of emergency communication, I am very sensitive to
>anything that would undermine the use and availability of CW, or that
>could add undue interference to the CW-only bands.
>
>CW is the single most effective mode of communication for low power
>stations, and permits low power (or low antenna) stations to use very
>narrow bandwidth filters to achieve superior Signal to Noise Ratio over
>all other modes of communication available in our hobby. Also, CW
>equipment, and accessories such as keyers or straight keys, are the
>least costly and simplest to build or purchase, thus making the hobby
>accessible and affordable to the broadest populations, including those
>who are new to electronics or have difficulty affording expensive
>equipment
or antennas.
>These constituents are vital to the long term growth of our hobby,
>since they will continue to invest and grow as they become more
>upwardly mobile and more engaged in the hobby. We must do all we can to
>protect their entrance and participation. Thus, for at least these
>reasons, we must do all we can to protect CW.
>
>I am opposed to RM-11708 in its current form, because the proposed
>ruling does not expressly indicate how CW operations will be
>sufficiently protected, and there is no acknowledgement of the vitality
>of CWs use for emergency purposes. The acknowledgement of the
>importance of protecting CW so that our hobby may be enjoyed and
>practiced by persons of moderate means also is not sufficiently
>addressed
in the proposed rulemaking.
>
>However, that said, I applaud the Leagues effort to push our hobby
>forward, and I would support a rule making that ensures CW is
>protected, and would suggest that the proposed rulemaking specify the
>use of broadband digital modes to be placed far enough away in the ham
>bands so as to not interfere with CW, and to explicitly state that
>these new digital modes will be made to co-exist with SSB signals in
>the SSB portion of the bands.
>
>In particular, l would support a band plan that allowed the wideband (3
>kHz) digital modes to occupy a chunk of spectrum in the upper part of
>the SSB band allocations in each of the HF bands.
>
>For example, if the newly proposed digital wideband modes were
>permitted in the very upper 25 kHz or 50 kHz of the SSB allocation,
>this would support the new modes, while keeping them sufficiently
>distant in spectrum from CW. An important point to note is that the
>bandwidths of the proposed digital modes are comparable to SSB
>bandwidth signals, thus making it most sensible to allow these new
>digital signals to be used in the current SSB spectrum allocation, and
>to be placed at the very upper band edges of the SSB allocation.
>
>Finally, the interference of a wideband (2.6 kHz) digital signal will
>be of the same order of the bandwidth of SSB signals, thus allowing
>interference to be channelized on a one to one ratio between a SSB user
>and a broadband digital mode user. To a first approximation, the power
>spectrum width and power density in a SSB or digital signal will be
>very comparable in bandwidth. Note that this is in stark contrast to
>the lack of parity in the CW bands, where several (up to 5 or more)
>separate CW signals could occupy a single wideband digital signal
>spectrum. In lay persons terms, an interfering Pactor signal could wipe
>out many CW conversations, yet it would only wipe out one SSB
>conversation. This is yet another reason to place the new digital modes
>at the very upper band edge of the SSB spectrum, as CW signals would
>suffer tremendously if they had to share the spectrum with broadband
>digital signals. Already, RTTY operation from domestic and overseas
>operators create harmful interference in the CW bands. We must avoid
further erosion.
>
>Thank you for the opportunity to comment, and thanks to all of you for
>promoting our wonderful hobby.
>
>73.
>
>Ted Rappaport, N9NB
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