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

POLICING THE ETHER 287
circuit crystal set capable of picking up stations beyond 50 miles, at a cost
of $15; and an electron-tube set, reaching out a hundred miles, for between
$23 and $37, including the tube ($5) and the storage battery ($15—$20).
Other Bureau letter circulars that spring and summer furnished sources of
elementary radio information to amateurs and described auxiliary con-
densers, loading coils, and an audiofrequency unit for receiving sets.194
Even before these letter circulars appeared as formal publications, they were
widely printed on the new radio pages introduced by newspapers every.
where.195 Altogether, in that first year of the radio boom the Bureau issued
almost a hundred reports, most of them typewritten or mimeographed, to
meet the demand for radio data and instruction of radio technicians.196
Available too was the Bureau's compendious Circular 74, "Radio instruments
and measurements," an encyclopedia of the theoretical and practical aspects
of radio measurements. Less than a year after the boom started so many
types of radio sets were on the market that the Bureau urged that a national
movement be launched for the standardization of radio apparatus and
service.'97
The proliferation of radio receivers attracted thousands of hopeful
station owners into the potentially lucrative broadcasting field, and for every
one that succumbed, two stood ready to take his place. But there was more to
it than building a station and selling air time even in those days. Of fewer
than a thousand channels or noninterfering wavelengths in the then utilizable
radio wave spectrum, only 89 were available to American broadcasting.
Interference between stations as some 500 of them competed in these wave-
lengths raised immediate difficulties, and became insufferable when, in order
to drown out competition and reach snore people, stations that could afford
it increased their power.'98
Since radio had long been used almost exclusively by ships, the
Federal Radio Law of 1912 had made the Bureau of Navigation in the
Department of Commerce responsible for licensing stations and assigning
wavelengths. It was a toothless law5 for Commerce could not deny or revoke
a license, and bills proposed by Commerce for "policing the ether" repeatedly
LC43 (Feb. 15, 1922) described the crystal set, LC48 (July 26, 1922) the vacuum
tube set. The other letters were LC39, LC44, and LC46.
C121, C122, and C133 were published in 1922; C137 and C141 in 1923. Two
commercial publishers not only reprinted C120, on the crystal set, but copyrighted their
booklet, and had to be enjoined. NBS Progress Report, May 1922 (NBS Box 24, PRM)
NBS Annual Report 1922, p. 56.
LC66 (June 1922) offered a partial list of almost 275 manufacturers and distributors
of radio receiving equipment.
late as 1928 most stations still operated on 500 watts, with some up to 1,000 watts.
The most powerful, 50,000 watts, had a radius of less than 500 miles. Schubert, The
Electric Word, pp. 223—224.