The Citizens Radiocommunication Service
March 1945 QST Article
hard to imagine a time when unlicensed radio frequency bands were
not the norm, but early in the history of radio, strict spectrum
control was necessary in order to prevent unintentional radiation
from crappy equipment from interfering with services. Remember that
even in the mid 1940s, many, if not most, casual users were cobbling
together their own transmitters and receivers from scratch. Transmitter
powers were easily high enough to interfere with nearby and distant
receivers, but even improperly shielded receiver oscillator ("exciters")
could cause interference with a neighbor's nightly Lone Ranger
March 1945 QST
Wax nostalgic about and learn from the history of early electronics. See articles
QST, published December 1915 - present. All copyrights hereby acknowledged.
Around 1945, the FCC began entertaining the idea
of allocating bandwidth for the use of the newfangled "walkie-talkies"
that were developed for field communications during World War II.
This 460 to 470 MHz band was the first of the Citizens' Bands that
eventually opened up in the 27 MHz realm, which was widely adopted
by the trucking industry in the 1970s. Cellphones are the latest
step in the evolution of license-free radio devices, occupying bands
in the 800, 900, 1800, 1900, and 2100 MHz bands.
Commission Proposes Walkie-Talkies for General Citizenry
Outside of the amateur allocations, the most interesting feature
to us in the Federal Communication Commission's report on its proposed
postwar allocations above 25 Mc. was its announcement of its intention
to create a new Citizens Radiocommunication Service for the use
of the general public under minimum licensing requirements.
We comment on this topic on this month's editorial page and
our purpose here is simply to present the Commission's own language
from its report, which tells the tale very well indeed:
"The development of light-weight portable short-range radio
communications equipment of the 'walkie-talkie' type has opened
the door to a large variety of new private applications of radio.
The success of such communications on the battlefront has been followed
by many suggestions for peacetime use of low-power portable
transceivers in the cities, on the highways, and in rural areas.
To make possible the fullest practicable development of private
radio communications within the limits set by other demands for
assignments in the spectrum, the Commission on its own motion proposes
to allocate the band from 460 to 470 Mc. to a new 'Citizens Radio-communication
"The possible uses of this service are as broad
as the imagination of the public and the ingenuity of equipment
manufacturers can devise. The citizens radiocommunications band
can be used, for example, to establish a 'physicians' calling service,
through which a central physicians' exchange in each city can reach
doctors while they are en route in their cars or otherwise not available
by telephone. Department stores, dairies, laundries and other business
organizations can use this service in communicating to and from
their delivery vehicles. Similarly, it can be used in communicating
to and from the trucks, tractors, and other mobile units operating
in and around large industrial plants and construction projects
- many of which spread over a number of square miles. It can be
used on farms and ranches for communications to and from men in
the fields; on board harbor and river craft; in mountain and swamp
areas, etc. Sportsmen and explorers can use it to maintain contact
with camps and to decrease the hazards of hunting, fishing, boating,
and mountain climbing. Citizens generally will benefit from the
convenience of this service by utilizing two-way portable radio
equipment for short-range private service between points where
regular communication facilities are not available. During emergencies
when wire facilities are disrupted as a result of hurricane, flood,
earthquake, or other disaster, the service, as has been demonstrated
by the amateur service, will be of inestimable value.
allocations are being made for urban and for rural transit
radio communications, which will be available for communicating
with city or intercity buses, trucks, taxicabs, etc. These services
may develop on a common carrier or private basis on the frequencies
set aside for those purposes. In either event, the citizens radio
communication band will be open to taxicabs, delivery vehicles,
or other mobile units, as well - as for incidental communication
between fixed points.
"Common carrier operation in
the Citizens Radiocommunication band will not be permitted,
and no charge can be made for the transmission of messages
or use of the licensed facilities. The service will thus be for
the private use of the licensee who will be responsible for the
use of the facilities under the regulations to be promulgated- by
"The 460-470-Mc. band which the Commission
proposes to allocate for this service is essentially adapted to
short-range communications, and as such, is admirably suited to
the uses proposed.. The rules will permit the use of 'booster' or
automatic relay installations where necessary. It is anticipated
that most transmitters on this bandwidth be of low power and
will not utilize extreme antenna heights. Higher power may be permitted
in rural areas where no interference will result.
of equipment for use in the citizens radio communication band should
challenge the ingenuity of radio designers and engineers. A combination
transmitter and receiver of reasonable weight can no doubt be mounted
in a suitcase; a broadcast receiver, an alarm system, remote control
systems, and other devices can perhaps be added to meet particular
needs. By keeping the rules and regulations to a minimum, the Commission
hopes to encourage ingenuity in design and in utilization.
"As in the case of the amateur service, the Commission proposes
to assign no channels within the band. It is reasonable to suppose
that most equipment will utilize a channel of 150 kc. more or less,
making possible some 60 or 70 channels; but, as in the amateur band,
these matters will not be determined. by rule or regulation. It
should be possible by the use of comparatively simple circuits already
known to provide both transmitters and receivers tunable over all
or most of the 460-470-Mc. range and emitting signals sharp enough
to minimize interference.
"The bands both above and below
460-470 Mc. are assigned to other services; but the allocation is
such that if the utility and requirements of citizens radiocommunications
warrant, the band can at some future time be expanded. Alternatively,
if a demand for assignments in this band does not arise, the band
can be reassigned to another service at a later date .
essence of this new service is that it will be widely available.
Accordingly, only the minimum requirements of the Communications
Act plus a few minimum traffic rules will be set up. Operator licenses
will be granted only to citizens of the United States., To procure
such a license, an applicant need only show familiarity with the
relevant portions of the Communications Act and of the simple regulations
governing this service. No technical knowledge will be required.
It is hoped that the license can be in the form of a small card,
with the operator's license on one side and the station license
on the other, and that these will remain in force for five years
with simple renewal provisions. Station licenses will be limited
to point-to-point, fixed point-to-mobile, mobileto-mobile, and
multiple-address communications; broadcasting is not contemplated.
"A concomitant of the widest possible availability is that
particular licensees are not accorded protection from interference.
A license in this service does not guarantee the right to a channel;
it affords rather an opportunity to share with others the use of
a band. The success of this arrangement in the amateur bands gives
every reason to believe that it will be equally successful in the
citizens radio communications band. In the event that intolerable
abuses arise, the Commission will of course take steps to eliminate
them. The 10,000 kc. width of the band will no doubt be sufficient,
however, to make possible simultaneous and efficient use of the
limited-range service for many purposes, with serious interference
limited to few if any parts of the country.
"In any areas
where serious interference is experienced, it is the expectation
of the Commission that various users of the band in a particular
community will jointly seek, perhaps through local organizations
similar to the American Radio Relay League in the amateur field,
cooperatively to solve local problems of interference and to ensure
maximum utilization. The new service is essentially a local service;
the problems will differ widely in an urban and rural area, in the
mountainous West and the flat Middle West, etc. The Commission is
prepared to cooperate with local groups which may be formed in the
working out of cooperative arrangements and it will resort to limiting
regulations only in the event that an imperative need is shown."
1996 - 2018
BSEE - KB3UON
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