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Old March 29th 08, 03:25 AM posted to rec.radio.amateur.moderated
Dave Platt Dave Platt is offline
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First recorded activity by RadioBanter: Jul 2006
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Default WPM to BPS calculation

In article ,
Klystron wrote:

I think of them as matters of economics and practical reality. To
wit: it should be obvious that we cannot have every possible mode
available on every band.


We can't have all of the modes, simultaneously, with an unlimited
number of users, on every band band, at the same time. Bandwidth is
limited - granted.

It does not follow from that, that we must be limited to a
strictly-enumerated set of modes at all times. The FCC used to assert
that this was the case, but has eliminated many of those constraints
in favor of an approach which favors more experimentation and
development.

Some limits must be imposed on the number of
modes and the way in which they share limited bandwidth.


I agree that a policy that users of the band must share bandwidth in a
reasonable and respectful way, is reasonable and proper.

I do *not* agree that this necessitates that only a specific set of
modes be allowed.

Again, if you can't fit every possible mode onto a given 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; some modes
will be authorized, while some other modes will be excluded. This goes
back to my claim that it is a matter of economics; it represents a
managed resource (a limited "supply") in the face of potentially
unlimited demand. It is from that perspective that I claim that old time
Morse zealots are impeding progress and are attempting to arrogate to
themselves a finite public good, much like cattlemen grazing their cows
on public grasslands while excluding others from using those public
lands for other purposes.


The portion of the band which is restricted to CW-only by the FCC is
*tiny* - small portions of the 2- and 6-meter bands, plus a portion of
80 which is CW-only for Novices and Technicians but not for anyone else.

Almost all of the non-phone portions of the band are *already* open to
various digital modulations (per the FCC regs and per the ARRL
bandplans and gentlepersons' agreements), and are quite extensively
used in that fashion today.

From where I sit out here in the cheap seats, your own attitude

strikes me as more zealous, and less willing to cooperate and share,
than what I observe in the people I know who operate a lot of CW.

Considering the small, aggregate size of the HF bands, can you offer
some suggestions as to how many modes can plausibly 'share the road?'


I don't think it's a question which can meaningfully be measured in
"number of modes". Some modes co-exist well, others do not.

I think it's a question of the number of _users_ of the band, at any
given time, and the type and quality of the conversations that they
can carry on.

What modes must be forbidden so that the modes that you like can be
allowed?


Well, I tend to agree with the FCC that broad-spectrum audio (e.g. SSB
with a DC-to-10-kHz bandwidth, or [worse] AM with a similar passband)
is excessively wide - it's using more bandwidth than is reasonable for
the conversation in question.

If you say that there are none, then perhaps we can have APCO
25, DV and DD on HF? What do you say to the hams who claim that AM
shouldn't be used on HF, because it uses to much bandwidth?


I think there's room for AM, and that SSB is more bandwidth-efficient,
and that the de facto practice of having AM operators voluntarily hang
out in a sub-portion of the HF band works pretty well.

I guess I just don't see why you're so intent on suppressing a mode of
operation which allows quite a lot of individual operators to carry on
multiple independent conversations within a limited bandwidth, at one
of the lowest potential equipment costs per operator of any mode.

Granted, other modes may get more *total* data traffic through the
same amount of spectrum width... but these modes tend to use more
spectrum width per conversation/session, and you end up with less
individual users of the band at any given time.

Applying a purely "economic" model to the ham spectrum (i.e. most
traffic per available Hz of bandwidth) rather misses the point, I
think, because it completely discounts all of the other values
(personal enjoyment, learning, development of personal skills and
knowledge) in ham radio. Ham radio is *NOT* a commercial service with
just a single agenda.

--
Dave Platt AE6EO
Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior
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