Radio celebrates 100
years.
Marconi
never claimed that he invented the radio all alone. There
were a number of others working in the field, from Nickola
Tesla to Nathan
B. Stubblefield, all of whom demonstrated communication without
wires. These other guys can take a walk, though.... because
Marconi is the one who put it all together. He demonstrated
his first wireless, in Italy, in 1895. He was the world's
first ham; an engineer and an ace tinkerer, with the managerial
smarts to found a gigabuck industry.
Most
people associate Marconi with his dramatic test of transatlantic
transmission, that gave wireless a permanent commercial role.
This didn't happen until 1901. The transmitter, a huge spark
coil, was in England, and the receiver, using an antenna held
high aloft by a kite, was in Newfoundland. The first signal,
sent one way, was a simple 'S' in Morse - three dits.
Marconi's first receivers
were coherers, a sort of crystal radio. Early antennas were
treated as giant "condensers" (capacitors), with
as much wire as was sane to hang as the "aerial"
half, and our mother Earth as the ground. At these wavelengths,
you couldn't put up too much wire. Radio stations tended to
be on rather large plots of land. Marconi, however, soon designed
the space-saving antenna that still bears his name, a vertical
with counterpoise, often operating at DC ground.
Marconi
Wireless contracted with many ships, including the Titanic.
This doomed vessel's radio call was MGY, the M standing for
Marconi. Titanic wasn't the first to use SOS, and in fact
sent initial calls with CQD, Marconi's original distress signal.
One of the two "Marconi Operators" survived the
sinking, and, despite frostbite, insisted on taking his turns
at Carpathia's key. Anyone who thinks that news media were
any different 80 years ago should look at some of the surviving
radiograms - "TALK TO NO ONE X WILL PAY TOP PRICE FOR
YOUR STORY AR" was typical!
Shoreside,
a young Marconi operator named David Sarnoff had just gotten
off his shift at the key when he saw headlines of the sinking.
He rushed back to the New York station to be of service. Later,
when Sarnoff had siezed Marconi Wireless in a Congressional
action, and when he had become the owner of mighty RCA, and
when he was thus the Bill Gates of his time, he boasted that
he'd personally copied Titanic's initial distress call. He
hadn't, but nobody argued with him...
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After
this disaster, a series of international treaties created the maritime
radio system that, more or less unchanged, saved lives and property
until February of 1999. Here we have 80 years of proud service by
real radio people, standing 24/7/52 watch at real radios, earning
their thunderbolts the hard way. Let's see the GMDSS appliance operators
top this record!
The early spark transmitters
just blasted, but tuned ones came quickly. They were huge, hundreds
of kW, and they caught fire regularly. Not much later, General Electric
set up a competing wireless network of giant stations using 200 kW
Alexanderson alternators. These huge electric generators, spun up
to high RPM, made AC at radio frequencies. There's still a working
one in Sweden, which is fired up a couple of times a year and copied
worldwide by those who can receive this low frequency signal. It is
one "hellacious" device.
Alexanderson
might have killed off King Spark all by himself, as Marconi was
interested in his alternators, but then there came a new gadget
called the radio tube (valve-see audion above). Early ones came
from the world's second ham, Lee de Forest, who never really did
understand just why the hell his Audion ever worked at all. De Forest
was confused all the way to the bank.
Marconi
quickly converted to his own, custom, transmitting valves. These
were heroic, hand-blown, glass bottles, resembling large chemistry
flasks. Wires came out of the ends. To get sufficient output, you
hung the required number of wires on a breadboard type of devicer,
connected the wires to the several bus bars, put in the electrodes,
and stood clear. Yikes!
The
wireless transmitter was the Internet of its time. It changed everything.
No wonder 1995 had a Marconi Centennial.
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