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Jagadish Chandra Bose and the invention of radio

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Feb 21, 2022, 4:44:28 PM2/21/22
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Radio was INVENTED by an Indian/Hindu Jagadish Chandra Bose but the EVIL
WHITE THIEVING FILTH claimed as their own, as usual.




By 1895, barely a year after starting his research, Bose made the first
public demonstration of radio waves in the Kolkata town hall. Details of
the apparatus used are vague, but at a distance of 75 feet, he remotely
rang an electric bell and ignited a small charge of gunpowder. The
invited guests were amazed by the demonstration that Adrisya Alok, or
“Invisible Light” as Bose would summarize it in a later essay, could
pass through walls, doors, and in a particularly daring feat of
showmanship, through the body of the Lieutenant Governor of Bengal.





https://swling.com/blog/2016/01/jagadish-chandra-bose-and-the-invention-of-radio/


Jagadish Chandra Bose and the invention of radio


J.C. BOSE AND THE INVENTION OF RADIO

The early days of electricity appear to have been a cutthroat time.
While academics were busy uncovering the mysteries of electromagnetism,
bands of entrepreneurs were waiting to pounce on the pure science and
engineer solutions to problems that didn’t even exist yet, but could no
doubt turn into profitable ventures. We’ve all heard of the epic battles
between Edison and Tesla and Westinghouse, and even with the benefit of
more than a century of hindsight it’s hard to tell who did what to whom.
But another conflict was brewing at the turn of 19th century, this time
between an Indian polymath and an Italian nobleman, and it would
determine who got credit for laying the foundations for the key
technology of the 20th century – radio.

Appointment and Disappointment

In 1885, a 27-year old Jagadish Chandra Bose returned to his native
India from England, where he had been studying natural science at
Cambridge. Originally sent there to study medicine, Bose had withdrawn
due to ill-health exacerbated by the disagreeable aroma of the
dissection rooms. Instead, Bose returned with a collection of degrees in
multiple disciplines and a letter of introduction that prompted the
Viceroy of India to request an appointment for him at Presidency College
in Kolkata (Calcutta). One did not refuse a viceroy’s request, and
despite protests by the college administration, Bose was appointed
professor of physics.



https://hackaday.com/2016/01/19/j-c-bose-and-the-invention-of-radio/

J.C. Bose And The Invention Of Radio

Dan Maloney


The early days of electricity appear to have been a cutthroat time.
While academics were busy uncovering the mysteries of electromagnetism,
bands of entrepreneurs were waiting to pounce on the pure science and
engineer solutions to problems that didn’t even exist yet, but could no
doubt turn into profitable ventures. We’ve all heard of the epic battles
between Edison and Tesla and Westinghouse, and even with the benefit of
more than a century of hindsight it’s hard to tell who did what to whom.
But another conflict was brewing at the turn of 19th century, this time
between an Indian polymath and an Italian nobleman, and it would
determine who got credit for laying the foundations for the key
technology of the 20th century – radio.

Appointment and Disappointment
Jagadish_Chandra_Bose
Jagadish Chandra Bose

In 1885, a 27-year old Jagadish Chandra Bose returned to his native
India from England, where he had been studying natural science at
Cambridge. Originally sent there to study medicine, Bose had withdrawn
due to ill-health exacerbated by the disagreeable aroma of the
dissection rooms. Instead, Bose returned with a collection of degrees in
multiple disciplines and a letter of introduction that prompted the
Viceroy of India to request an appointment for him at Presidency College
in Kolkata (Calcutta). One did not refuse a viceroy’s request, and
despite protests by the college administration, Bose was appointed
professor of physics.

Sadly, the administration found ways to even the score, chiefly by not
providing Bose with any laboratory space, but also by offering him only
100 rupees a month salary, half of what an Indian professor would
normally make, and only a third of an Englishman’s salary. Bose
protested the latter by refusing salary checks – after three years his
protest worked and he got his full salary retroactively – and worked
around the former by converting a tiny cubicle next to a restroom into a
lab. But in those 24 square feet, equipped with instruments of his own
design and paid for at his expense, Bose would work wonders and begin to
engineer the embryonic field of radio.

At around the time Bose joined Presidency College, Heinrich Hertz was
confirming the existence of electromagnetic waves, postulated by James
Clerk Maxwell in the 1860s. Maxwell died before he could demonstrate
that electricity, magnetism, and light are all one in the same
phenomenon, but Hertz and his spark gap transmitters and receivers
proved it. Inspired by this work and intrigued by the idea that
“Hertzian Waves” and visible light were the same thing, Bose set about
exploring this new field.


By 1895, barely a year after starting his research, Bose made the first
public demonstration of radio waves in the Kolkata town hall. Details of
the apparatus used are vague, but at a distance of 75 feet, he remotely
rang an electric bell and ignited a small charge of gunpowder. The
invited guests were amazed by the demonstration that Adrisya Alok, or
“Invisible Light” as Bose would summarize it in a later essay, could
pass through walls, doors, and in a particularly daring feat of
showmanship, through the body of the Lieutenant Governor of Bengal.

Bose’s wireless demonstration was remarkable for a couple of reasons.
First, it took place two years before Marconi’s first public
demonstrations of wireless telegraphy in England. Where Marconi was
keenly interested in commercializing radio, Bose’s interest was purely
academic; in fact, Bose flatly refused to patent nearly all of the
inventions that would spring from his tiny workshop, on the principle
that ideas should be shared freely.

The 1895 demonstration also used microwave signals instead of the low
and medium frequency waves that Marconi and others were working with.
Bose recognized early on that shorter wavelengths would make it easier
to explore the properties of radio waves that were similar to light,
like reflection, refraction, and polarization. To do so, he invented
almost all the basic components of microwave systems – waveguides,
polarizers, horn antennas, dielectric lenses, parabolic reflectors, and
attenuators. His spark-gap transmitters were capable of 60GHz operation.

Some of Bose’s most important work in radio concerned detection of
electromagnetic waves. Early wireless pioneers had discovered that
electromagnetic waves could be rectified by fine metal particles
contained in a tube between metal conductors; the electrical energy
would cause the particles to clump together and become conductive. The
device was called a coherer because of the clumping action and was used
as rectifiers in all the early practical wireless receivers, despite its
operation being not well-understood. Experiments with coherers continue
to this day.

Early coherers had a problem, though – the filings stayed stuck together
after the signal had passed. The device needed to be reset by a tiny
electromagnetic tapping mechanism that jiggled the filings back into a
non-conductive state before the next signal could be detected. This had
obvious effects on bandwidth, so the search for better detectors was on.
One improvement invented by Bose in 1899 was the iron-mercury-iron
coherer, with a pool of mercury in a small metal cup. A film of
insulating oil covered the mercury, and an iron disc penetrated the oil
but did not make contact with the liquid mercury. RF energy would break
down the insulating oil and conduct, with the advantage of not needing a
decoherer to reset the system.

Bose’s improved coherer design would miraculously appear in Marconi’s
transatlantic wireless receiver two years later. The circumstances are
somewhat shady – Marconi’s story about how he came up with the design
varied over time, and there were reports that Bose’s circuit designs
were stolen from a London hotel room while he was presenting his work.
In any case, Bose was not interested in commercializing his invention,
which Marconi would go on to patent himself.

The Father of Semiconductors?
Early Bose galena point-contact detectors. Source: National Radio
Astronomy Observatory
Early Bose galena point-contact detectors. Source: National Radio
Astronomy Observatory

Bose also did early work in semiconductor detectors. Bose was exploring
the optical properties of radio waves when he discovered that galena, an
ore of lead rich in lead sulfide, was able to selectively conduct in the
presence of radio waves. He was able to demonstrate that point contacts
on galena crystals worked as a better coherer, and in an
uncharacteristic move actually patented the invention. Interestingly,
the patent includes descriptions of substances that show either
decreased or increased resistance to current flow with increasing
voltage; Bose chose to describe these a “positive” and “negative”
substances, an early example of the “P-N” nomenclature that would become
common in semiconductor research. Decades later, William Brattain,
co-inventor of the transistor, would acknowledge that Bose had beat
everyone to the punch on semiconductors and would credit him with
inventing the first semiconductor rectifier.

Inventions and innovations would flow from Bose’s fertile mind for many
decades. He eventually turned his attention to plant physiology,
studying the stress responses of plants with a sensitive device he
invented, the crescograph, which could amplify the movements of the tips
of plants by a factor of 10,000. Not surprisingly, he also did important
work on the effects of microwaves on plant tissues. Bose also did work
comparing metal fatigue and fatigue in physically stressed plant
tissues. Bose is also considered the father of Bengali science fiction.

Bose is rarely remembered as a pioneer in radio, despite all he
accomplished in engineering the wireless system that would eventually
stitch together the world. Given his position on patents, that’s not
surprising – his inventions were his gift to the world, and he seemed
content with letting others capitalize on his genius.

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