KB6NU's Ham Radio Blog

///////////////////////////////////////////
How the National Bureau of Standards helped make "radio"

Posted: 21 Feb 2020 06:22 AM PST
http://feedproxy.google.com/~r/kb6nu...m_medium=email


This was originally published on the National Institute of Science and
Technologys blog, Taking Measure.

NIST’s Role in the Early Decades of Radio (1911-1933)

Even if you weren’t able to watch the recent Super Bowl on TV, you could
still listen to the play-by-play commentary on the radio. But radio does
more than just broadcasting sporting events or playing music. It plays a
major role in emergency response, navigation and science.

The word “radio,� however, didn’t become part of our regular vocabulary
until 1911, and it happened thanks in part to J. Howard Dellinger, a radio
scientist at the National Bureau of Standards (NBS), the agency that became
the National Institute of Standards and Technology (NIST). This came about
when the second International Radiotelegraph Conference was being planned
in London, and a professor sent Dellinger a paper that he was going to
present to the conference for review.

At the time, “wireless� was used as the term for radio communication,
especially by the British. However, NIST was charged with revising
standards in preparation for the conference, and Dellinger suggested that
the professor use “radio,� which was already becoming a popular word in the
U.S., instead of “wireless.� The professor agreed, and the word “radio�
went on to become the universally accepted term.

Dellinger not only played a role in popularizing the word “radio,� but he
also played a role in the first radio work done at NIST. A commercial
company asked NIST to calibrate a wavemeter, a device developed by one of
its engineers that measures electromagnetic waves like those of radio.
Dellinger was known as the wireless expert and took on the project of
calibrating the first radio instrument at NIST.
A New Type of Radio Receiver

But for radio to become mainstream, it first had to be commercialized,
which began with its introduction into households. However, the challenge
was building a radio set that used the electrical current, called
alternating current (AC), which powered lights, fans and kitchen appliances
when plugged into wall sockets. The predecessor to this technology was
developed and patented by two researchers, Percival D. Lowell and Francis
W. Dunmore, at NBS in 1922. They called their invention the “mousetrap.�
Percival Lowell with his patented radio set powered by alternating current.
Credit: NIST

The “mousetrap� was a receiver for a radio amplifier that could run on AC.
This was considered a breakthrough because at that time radios were only
able to be powered by direct current (DC) provided by batteries. These
batteries were bulky and heavy, had to be charged from time to time and
were considered dangerous because of the acid used in them. The
researchers’ prototype meant the radio could be used in homes without
causing damage and with the same performance quality.

Lowell and Dunmore filed two more patents together for other innovations,
and for the “mousetrap� they sold the rights to the Dubilier Condenser
Corporation. Little did they know that, because there was no uniform policy
on patents issued to government employees, their actions would result in
more than a decade of litigation over who legally had the rights to the
patent.

While they were tied up in court, the Radio Corporation of America (RCA)
developed its own model of the AC radio in 1926. Its model later became the
first AC-powered radio sold to consumers.
Flying by Radio

During the early years of flight navigation, NIST was doing research to
assist pilots while they were flying and landing. Pilots needed three
things to get their bearings when flying “blind,� meaning it’s foggy, too
dark or too cloudy to see. They needed to know the longitudinal position,
altitude and speed of the aircraft, which were all achieved by various
beacons installed in the plane. The remaining issue was that there were two
frequencies the pilot constantly had to switch between the frequency that
the Department of Commerce used to send weather information to planes and
ships, which sometimes caused interference for pilots, and the frequency
the radio beacon operated on, which gave altitude and other information.

Dunmore created a prototype, but Harry Diamond, a radio engineer who joined
NIST in 1927, completed the device, called the radio guidance system.
Diamond solved the problem by developing a separate device that allowed for
voice communication to the pilot without receiving any outside interference
from ships’ radios.

A Curtiss Fledgling, a trainer aircraft developed for the U.S. Navy, was
equipped with the device, and flight tests were performed between NISTs
experimental air station at College Park, Maryland, and Newark Airport in
New Jersey in foggy weather. After a series of successful tests were
performed, the device was turned over to be used by the Department of
Commerce in 1933.
Praise From a Famous Inventor

While mostly intended for serious users, some of NISTs journals and
publications were popular with the public. One such book, titled The
Principles Underlying Radio Communication, covered topics such as
elementary electricity, radio circuits and electromagnetic waves and was
also published as a textbook for soldiers in the U.S. Army. The famous
inventor Thomas Edison received a copy from NIST and wrote a letter
thanking the first director, Samuel W. Stratton, for publishing it, saying
it was “the greatest book on this subject that I have ever read.�

As these and other examples show, NISTÂ*hadÂ*a significant influence on radio
research between 1911 and 1933. However, NIST’s radio work didn’t end with
the first blind landing. NIST would continue to contribute to the field
leading up to and during World War II, and research continues to this day
in areas such asÂ*5G,Â*public safety communicationsÂ*andÂ*spectrum sharing.


ABOUT THE AUTHOR

Alex Boss is a general assignment writer in the NIST Public Affairs Office
and covers standard reference materials (SRM). She has a B.S. in biology
from Rhodes College and an M.A. in health and

The post How the National Bureau of Standards helped make radio appeared
first on KB6NUs Ham Radio Blog.