WPM to BPS calculation
On Mar 28, 4:46�pm, Klystron wrote:
(Dave Platt) wrote:
I do, however, object in principle to the idea that these are the
highest (or only) criteria, or that they're somehow sacred. �
� �I think of them as matters of economics and practical r
wit: it should be obvious that we cannot have every possible mode
available on every band.
Well, not every *possible* mode.
Some limits must be imposed on the number of
modes and the way in which they share limited bandwidth. This is one of
the reasons why the FCC exists.
Of course. But there are other factors, such as how popular a mode is,
how much bandwidth it occupies, how it is implemented, etc.
This is one of the (ostensible) reasons
why digital modes were not allowed for many years.
Please elaborate, particularly on the dates and where you got thise
The information I have seen says that the main reason FCC limited the
modes amateurs could use was that FCC has to be able to monitor
amateur transmissions. So if they allowed hams to use a new mode,
their monitoring stations had to be able to decode it.
45.45 baud 5 level Baudot RTTY was authorized for amateurs in the USA
about 1948. Analog SSTV (an image mode) followed in the very early
In the late 1970s-early 1980s, new monitoring equipment made it
possible for FCC to decode lots of modes, so US amateurs were
authorized to use ASCII RTTY, AMTOR, packet, and lots of other modes.
We're talking 20-25 years.
Of course not all modes are well-adapted to all bands. HF packet as
used by amateurs turned out to be a bit of a bust, due to being ill-
suited to HF propagation. PSK31, OTOH, has been a big hit.
The biggest impediment to digital modes in the ARS, IMHO, is the cost
of implementing them. Inexpensive PCs and "soundcard modes" have
changed all that.
And, I also object to the idea (which I think is implied by the tone
of your other messages - please correct me if I'm wrong) that
choice of communication methods is somehow exclusive...
that the fact
that a method which is superior (by your criteria, perhaps)
other methods that you find inferior should be wiped out or
abandoned... or that people who prefer to use the other
somehow responsible for Holding Back The True Progress.
My own perspective is that people may have *many* criteria
a means of communication (by radio or otherwise). �
bandwidth*reliability is not the sole criterion that people use, in
practice, nor do I think there's any reason that it should be. �
is full of tradeoffs between different criteria - information
bandwidth per Hz of spectrum, robustness of encoding,
multi-point communication, resistance to different sorts of
interference, cost of equipment, availability of equipment,
forth. �I communicate with my wife by voice, by email, by
by scribbling half-illegible notes on scraps of paper,
and by bringing
home flowers... different methods, for different
types of information-
passing under varying conditions.
� �Again, if you can't fit every possible mode onto a give
band (by the
way, every possible mode means exactly that,
not just modes that are
commonly used by hams - otherwise, we would have APCO 25,
in addition to
DV, to give just one example). Therefore, we must prioritize;
will be authorized, while some other modes will be excluded.
back to my claim that it is a matter of economics; it represents a
managed resource (a limited "supply") in the face of potentially
With all due respect, I think you are avoiding the question. Under
current FCC rules, almost any conceivable mode can be used on the
amateur bands if it is properly documented, does not involve
encryption, and is reasonably spectrum-efficient.
Look at how PSK31 came to amateur radio for an example. It was
developed by hams, not manufacturers. It's relatively easy to
implement without a big investment of special equipment, it's well-
adapted to HF conditions and spectrum-efficient. Most of all, a
considerable number of hams find it to be fun.
It is from that perspective that I claim that old time
Morse zealots are impeding progress and are attempting to
themselves a finite public good, much like cattlemen grazing
on public grasslands while excluding others from using
lands for other purposes.
How have "Morse zealots" done what you claim? In the US regulations,
there are no Morse-code-only segments of the HF bands - all are shared
with either data modes or voice modes. Every Hz. And it's been that
way at least 46 years.
Except for 2.5% of 6 and 2 meters, all of VHF/UHF and 160 are wide
open to all authorized modes for the various bands.
How are Morse-Code-using hams doing what you claim?
The cows-grazing-on-public-land analogy isn't really valid, because
amateur radio isn't a commercial venture, nor does the use of one mode
damage the band for use by others at a later time.
Try this one:
The amateur bands are like a public park system. Some are small, some
are large, some easily accessible, some remote. Depending on their
characteristics, different parks/bands are used for different
activities at different times. The question is how to best allocate
the resources to accomodate those who want to use them.
In commercial communications and public-safety,
bandwidth (or payload)
and reliability and cost all play a big factor. �In military
communications, reliability and security seem big, bandwidth is
important, and cost (of equipment at least) tends
to take a back seat.
Ham radio is a much more diverse motivation-space.
optimize their operations as for public safety and
EMCOM folks), others for "most distance per watt"
or "per dollar spent
on the radio" (QRP folks, homebrewers, and other
others for portability, others for plain ordinary fun (according to
their own definition of fun... for some folks,
crystal-oscillator transmitters is just what gets their rocks off :-)
There's plenty of room in ham radio for different modes of
Saying that we all *have* to abandon Morse (or SSB, or
voice, or AM,
or...) and strap computers to all of our rigs, in order to
experimentation and use with newer modes, is really missing the
point... it's implicitly denying a large percentage of hams
to explore those aspects of ham radio that *they*
find interesting and worthwhile.
That's exactly the point. Well worth repeating!
If we were all being paid to do all of this stuff, then the people
paying us would perhaps have the right to set our
agendas. �We aren't
(and by the rules of the game, cannot be... at least,
not here in the
US) and so we get to set our own priorities, operating-mode and
� �Considering the small, aggregate size of the HF bands,
can you offer
some suggestions as to how many modes can plausibly
'share the road?'
That depends on the modes and their characteristics. For example, it's
not a good idea to allow 30 kHz FM voice on 40 meters, because that
band is only 300 kHz wide, but the same mode is fine for VHF/UHF
What modes must be forbidden so that the modes that
you like can be allowed?
If you say that there are none, then perhaps we can
have APCO 25, DV and DD on HF?
If they meet the criteria of not being encrypted, being suitable
for HF use, and being reasonably spectrum-efficient, why not?
As long as they are grouped with similar modes, what's the problem?
What do you say to the hams who claim that AM
shouldn't be used on HF, because it uses to much bandwidth?
That depends on how "too much bandwidth" is defined. Certainly
transmitting hi-fi AM that's 10-15 kHz wide on a busy HF band is
spectrum-inefficient and inconsiderate. OTOH, good-quality voice AM
can be had in 6 kHz or so, and when a band is not too busy, why not
use it? Similar
It seems odd that "Morse zealots", whose favorite mode uses only a few
hundred Hz at most, are being held responsible for "impeding
progress", when most of the HF amateur bandspace in the US are
allocated to voice modes that take up much more spectrum.
Should hams stop using Morse Code? Or any other mode they now use?
73 de Jim, N2EY