Measures for Progress: A History of the National Bureau of Standards

NEW THINGS IN RADIO COMMUNICATION 197
the standards themselves "handled with a care and reverence that was
comparable with that given to the prototype platinum-iridium standard
meter bar." 87 Basic too was the Bureau work on the new electron or
vacuum tube.
With patent litigation suspended, radio manufacturers turned out large
numbers of these tubes as generators,. detectors, amplifiers, and modula-
tors of radio waves and other electrical currents. (Some of the early tubes
were as large as the wall telephones then in use.) Most of them went into
the radio communication apparatus constructed in the Signal Corps and
Navy radio laboratories at the Bureau and produced in quantity for these
services by the electrical industry.88 The Bureau measured the character-
istics of both experimental and production tubes, devised test methods and
apparatus, standardized certain types of tubes, and made studies of their
behavior in a variety of circuits.89
Of special importance in its work with vacuum tubes were the first
Bureau studies of such phenomena as the effects of diurnal fluctuations,
solar activity, and atmospheric electricity on radio communication. Out of
this work in the postwar years came wholly new concepts of the dimensions
of radio, as well as new standards of radio measurements.9°
Wartime research on the electron tube, which had previously been
little more than an artifact of the radio experimenters in this country, made
possible reliable long-distance wire telephony, as well as speech communica-
tion between ground stations and airplanes. Incorporating the vacuum tube
in the direction finder made it a convenient and portable apparatus that was
to prove as useful in detecting transmitting stations violating radio laws
as it was in guiding planes and ships through fog. In its role as an amplifier,
the vacuum tube permitted for the first time very small antennas, and by
greatly extending the range of radio communication ushered in the age of
radio.
That age did not, as might have been expected, begin with the arm-
istice. It was delayed first by the threat of Government ownership and then
by renewal of the patent wars of the radio industry. Under the widely held
87 Southword, Forty Years of Radio Research, p. 34.
88 For the wartime Navy research at the Bureau in long-distance communication, see
report of L. W. Austin in J. Franklin Inst. 193, 437 (1922), and NBS Letter Circular
(LC) 194 (Mar. 10, 1926).
A discovery made at that time in the idiosyncrasies in vacuum tubes, since known
as the "Miller effect," was first published in John F. Miller's "Dependence of the
input impedance of a three-electrode vacuum tube upon the load in the plate circuit"
(S351, 1919). See also NI3S Annual Report 1919, pp. 65—66, and F. Langford Smith,
ed., The Radiotron Designer's Handbook (Sydney, Australia: Wireless Press, 3d ed.,
1940), pp. 46—48.
"War Work," pp. 233—242.