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Old April 20th 07, 11:56 PM posted to rec.radio.amateur.moderated
AF6AY AF6AY is offline
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Default Before and After Cessation of Code Testing

Michael Coslo wrote on Fri, 20 Apr 2007 11:39:39 EDT

wrote:
On Apr 19, 11:47?pm, AF6AY wrote:


? ?1. ?"Discovery of 'shortwaves' enabling worldwide communications:
? ? ? Already known by non-hobbyist technologists.


Which ones? And why weren't they *using* those shortwaves before
amateurs led the way?


I think you two are both correct. 8^)


Regardless of the question marks added into my quotation (which
I never wrote with leading question marks), I will cite two
references which are obtainable:

1. Thomas H. White's early radio history web pages which include
many references and references with direct links. [try Searching
since Mr. White's website has had different names although his
content remains intact and expanded]

2. Hugh G. J. Aitken, "The Continuous Wave, Technology and
American Radio, 1900-1932," 1985, Princeton University Press.
My soft-cover copy is courtesy of Al Walston, W6MJN. In
particular Chapter 5. [University libraries might have this]

There is a lesser-known, harder-to-find overall history of
electronics (includes radio) published by McGraw-Hill's bi-
weekly subscription periodical Electronics, 17 April 1980,
a commemorative Fiftieth Anniversary edition (over 900 pp)
which takes an all-inclusive overview of all electronics from
before the first demonstration of radio in 1896 up to 1980.

From those three I've come to the conclusion that the forcing
of radio amateurs in the USA to "below 200 meters" (above 1.5
MHz) was purely and simply politics of the day. It should be
no surprise to know that radio use insofar as frequencies was
little more than chaotic before 1920, little more than that
during the entirety of the 1920s decade. Broadcasters wanted
what we now know as the "AM broadcast band" for their exclusive
use. Actually, that was a legitimate desire since broadcasters
would serve millions of citizens, not just a few thousands of
radio amateurs at the time.

Politics of the times did not stop with broadcasters versus
amateurs. For almost two decades the United States Navy
wanted to have regulatory control over all radio use! Marconi
desired a monopoly on worldwide radio use, including inroads
to control of all United States radio production and services.
The latter led a circuitous route to the establishment of the
Radio Corporation of America, originally as a sort of "patent
controller" or "quasi-repository" about radio in the USA. It
was a chaotic decade those 1920s, including many patent fights
in courts, and not much standardization in theory, components,
use, or services to citizens. See the proposal of President
Franklin Roosevelt to Congress to establish the Federal
Communications Commission to consolidate radio and telegram
regulations of 1933 and 1934, found on the FCC website.

It looks like a difference of
basic versus applied knowledge. That the shortwaves and much much higher
frequencies were known is not in doubt. Scientists were doing research
in GHz range frequencies surprisingly early on.


Heinrich Hertz did his basic research on radio waves using
what now appears to be VHF and UHF. He had no equipment to
measure such frequencies to any great precision. Lee de Forest
did some early work on transmission lines in an attempt to get
"a handle on" the behavior of higher radio waves on them. James
Clerk Maxwell postulated some physical laws and equations which
are applicable to all radio frequencies today, but he had almost
NO "test equipment" other than very simple experimental kluges
and brilliantly-applied logic to his "Laws."

The first radar experiments and first working radars worked on
VHF-UHF. It took a coordinated, consolidated group, forced by
needs of winning WWII at the "Radiation Laboratory" to really
get into the GHz frequency region.

Amateurs were forced to use frequencies that unknown to them or the
best minds of the time (could be both at once) discovered a lot of
unexpected characteristics of those higher frequencies.


As I originally wrote, it was fortuitous for radio amateurs to
be forced upward in frequency beyond 1.5 MHz. Those documented
demonstrations "got the ball rolling" for academicians and
researchers to study the ionosphere in detail. With scientific
proof, the commercial and government users took to HF in great
numbers by the 1930s.

I think that we'll find that time and again, restrictions lead to
innovation.


That's too broad a statement. Innovation and invention comes
from those individuals who dare to "push the [performance]
envelope" of most anything. The Wright Brothers weren't
exactly "restricted" in anything but laws of physics concerning
aerodynamics...so they built their own "wind tunnel" and got
basic information for themselves. But, could anyone have
thought ahead 50 years past their first heavier-than-air flight
in a wood-wire-fabric biplane, to trans-sonic speed metal
aircraft carrying more than two people?

In comparing "radio sets" of various times, examine the size,
weight, function, and features of today's amateur radio
transceivers with those of 1957. Or antennas, or test
equipment for measuring both. The advancement on both
technology and use is hand-in-hand and driven by market
forces more than anything. It is all interconnected and
one innovation can lead to others. James Burke's "Connections"
PBS-TV series is an excellent showing of the interconnection
of innovation and invention that can lead to surprising
improvement in improbably-related activies.


If the effectiveness of shortwave radio was known by nonamateurs,
why didn't they use it until after amateurs pointed the way and proved
it by their pioneering success?


A combination of ignorance (thinking that the higher frequencies were
of no use) and simply "betting on the wrong horse". is the answer AFAIAC.


The following is a quote from "Single Sideband, Principles and
Circuits" by Pappenfus, Bruene, Shoenike (Collins Radio), McGraw-
Hill 1964, paragraph 1-4, page 10:

"Since 1923 when the first r-f transatlantic SSB link was
established to England, there has been widespread use of pilot-
carrier and suppressed-carrier SSB by communications companies.
The severe static that prevailed at low frequency limited the
usefulness of the early radio links; but until the installation
of a v-f cable, no other communication circuit to Europe
approached the day-to-day reliability of the 55-kc ground-wave
signal. The frequency range below 500 kc because of its
freedom from propagation variation and signal "blackout," has
a consistency of received signal desireable in maintaining
telephone communication. However a number of disadvantages
are present that offset the signal reliability of the l-f
range. Disadvantage include high power, and need for large,
expensive antennas. The problems of vlf communications links
and l-f bands forced the expansion into and the development of
radio-communication links in the so-called short-wave bands
above the [AM] broadcast band."

Page 234 of the "Collins SSB Book" state that one of the
first applications of SSB to the HF bands was by the
Netherlands Telegraph Administration in 1934. This was
the Netherlands to the Netherlands Antilles (off the coast
of South America). [diagram of receiver on page 235]

Note: Commercial and government SSB is basically on the
USA telephony model C "carrier" frequency-multiplexed
four-voice-bandwidth system using 12 KHz bandspace.
Single-channel, 3 KHz bandspace SSB did not see great
numbers until the USAF SAC requirements were made after
WWII's end. "Pilot carrier" is in reference to a between
channel tone frequency deliberately sent as an early AFC.

Commercial and government communications users generally
plan for long service life, such service having reliability
and with known characteristics. While those may appear
conservative, those major players in communications aren't
in there for fun or experimentation. They are there for
the "long haul," both in distance and in time. Such long-
lived expectancy must be based on known information
supporting its development.

The Amateurs were confined to that area, and the experimentally
inclined did their experiments, and viola, a lot of discoveries and
advancements were made. It is a great story, and Hams should be proud of
that part of their history.


It is fine to be proud. However, history is the past.

As a more mature technology today, I wouldn't expect many more earth
shaking discoveries from Hams.


I disagree. The state of the art of all communications is
continually advancing. Radio development didn't stop prior
to WWII nor at any time up to now. For example, look at
PSK31 by G3PLX, D-Star by the JARL with support of Japanese
industry, APRS utilizing GPS downlink, all examples of post-
1980 innovation in amateur radio, done by radio amateurs for
radio amateurs.

The first reference I have to "repeaters" in radio (other
than specific radio relay sets) is in the TM for the
military AN/PRC-6 HT (includes a special cable set for
that purpose) printed about 1952. The U.S. military has not
used "repeatering" of that kind afterwards but look at the
large installation of ham repeaters in the USA of today!
Adoption and innovation of existing schemes and technology
in other radio services is no crime nor moral flaw. I think
that should be rewarded and praised equally well; some of
those adoptions/innovations are more complex and intellectual
(at least to me) than most of the early radio "pioneering" of
pre-WWII times.

With today's evidence of explosive growth in all electronics
there is a blurring between "who uses what in where" as to
both technology and use of radio. Both seem to circulate
in most radio services without regard to who was "first" but
rather can "I" [in a radio service] use it? Better yet, can
"I" adapt it for "my" radio service? Maybe, maybe not. It
might be worth a try. Falling back on "tried-and-true"
methods and holding fast to those seems counterproductive...

73, Len AF6AY