First, I do agree with N9NB that there needs to be a bandwidth limit in
the amateur bands - this has been confirmed by the FCC in numerous
communications and opinions about overly-wide phone signals and also by
97.307(f)(1) which limits the modulation index of angle-modulated phone
emissions to less than 1 at the highest modulating frequency. Clearly,
the idea of a maximum bandwidth is considered good practice in the phone
sub-bands and a similar limit in the RTTY/data sub-bands does not need
to strangle technical innovation. Nevertheless, it is not sufficient to
rely on the "necessary" and "good practice" wording in 97.303(1) because
neither is strong enough to be meaningful without creating endless
arguments and perceived loopholes. So just place a reasonable "roofing
bandwidth" on amateur radio emissions below 30 MHz - 3 kHz? 6 kHz? 10
kHz? - and let us sort it out as we do every day!
[If the maximum bandwidths of phone and data signals are to be linked in
one rule, a simple administrative fix could be made by the very simple
change of applying 97.307(f)(2) to all of the HF bands - renumber it
from 97.307(f)(2) to 97.307(g) or add (2) to all of the HF bands in
97.305. Digital voice would remain confined to the phone bands because
even though it is transmitted as bits, the overall package is still
classified as a phone emission, just as digitized images are still
considered image emissions (facsimile). (See 97.3(c) and 2.201)]
Let's get a grip, though...in my opinion:
PACTOR 4 is already permitted everywhere else in the world and has not
ruined ham radio yet. PACTOR 3 and PACTOR 4 modems are expensive - the
rush to use >$1000 modems to exchange non-commercial traffic at <10 kbps
(at best less than 1/5th of dial-up rates) over HF is not a very strong
business case. While it is popular to gnash our collective teeth about
those impure "boaters," (Oh, the fiends, checking their stocks via
amateur radio!) the primary use of the Winlink system is rapidly
shifting toward emcomm/public service, which is prominent in our Basis
and Purpose of 97.1(a). Using faster modems actually reduces band
occupancy in terms of Hz-sec for any particular message - although
better performance *might* increase the number of messages. But at <10
kbps and with the horrible things that HF does to a channel...I just
don't see a stampede materializing.
More importantly, ham radio needs to get with the program - our
over-reliance on decades-old analog modes is laughable. You want new
technical blood to fulfill 97.1(d)? Try explaining to anyone under 40
that our primary HF digital modes run at 31 baud or use the 80-year-old
5-bit Baudot code developed for electromechanical printers and which
can't even handle the full alphanumeric character set. Inform them of
our 300-baud symbol rate limit below 30 MHz and, after their initial
disbelief, you will get a look of pity followed by complete
disinterest. In most student papers at engineering conferences
everything under 1 GHz is considered BASEBAND AUDIO!
Nor is it a good idea to further splinter the ham bands - it just
creates unreasonable expectations of ownership or occupation. Many
operators discovered during the W1AW/portable year how channelized 40/75
meters had effectively become, simply due to squatter's rights. We are
always pooh-poohing band plans during contest weekends - rightfully -
and any kind of reserved-for-narrowband allocation will simultaneously
create the expectation that narrowband signals stay within it. There is
lots of room on the bands for all kinds of signals if we could only get
over the notion of reserved sub-bands, calling frequencies, net lists,
and been-here-for-years. We have these Big Knob thingies we can use.
We're not rockbound any more. Frankly, I think the whole notion of band
plans needs to be greatly de-emphasized. We are the most flexible
telecommunication service of all - why are we so intent on throwing that
away?
Consider the use of "smart spectrum" SDR-based displays showing where
all the signals of various types are and aren't. (The RBN almost does
that now...) With so many different modes and more on the way, it seems
to me that approach is a better way of going forward in line with the
"cognitive radio" approach to spectrum management and our mandate in
97.1(b) and (c). Alternatively, if the bands are going to be
segregated, then do it according to behavior (see my Contest Update
editorials of Sep/Oct 2005) which is the root cause of most inter-mode
conflicts, anyway.
A real problem that has been identified by many, and which is something
we really *do* need to address for *all* modes, is transmitter linearity
and noise. We have fantastic receivers that can hear a skeeter fart but
the bands are full of our own trash from non-linear and noisy
transmitters - even the expensive ones. (That we are still dealing with
key clicks in the year 2016 is ridiculous.) There are plenty of
techniques that we could adapt from the wireless data industry, such as
pre-distortion and higher-voltage final transistors, all
well-characterized mature technologies. The linearity issues with
complex I/Q data signals are the same as for speech modulation. Let us
solve noise and transmitter IMD and it will be a lot easier for
everybody to get along. Digital modes can be a lot more noise-tolerant,
too, and that might help a lot with the new reality of all spectrum,
just as FM was invented by Armstrong in response to AM static.
Also...this CW...I turn on my radio most weekdays and wonder where is
this precious commodity we are trying to preserve? Sure - contest
weekends sure load up the bands - but the other 90%+ of the time the CW
areas are pretty empty. I love CW but I am not of the opinion that we
have to hobble the service and keep it increasingly technically
irrelevant in order to preserve a century-old mode that isn't the
backbone of the service it once was.
The sky is not going to fall. Yes, I will swear like a sailor when a
data signal wipes out my CW run frequency, but then I'll use my Big Knob
and start again somewhere else. (Or just stay there and duke it out.)
Ham radio needs to accommodate useful data modes if it is going to
survive to celebrate its second century.
73, Ward N0AX
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