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Technical Topics => Part 15 AM and FM Station Operation => Topic started by: tybee on June 10, 2022, 2337 UTC

Title: Annual Fcc Report concerning Part15 1939-1960
Post by: tybee on June 10, 2022, 2337 UTC
An interesting and/or entertaining summery of part 15 cases as told by the FCC in their Annual Reports between 1939-1960

1939:
 - As a result of the increased use of many different types of low-power radio frequency electrical devices for alarms, phonograph -record -playing and remote- control purposes, an informal engineering conference was held at the Commission's offices in Washington on September 19 , 1938 , for the purpose of considering proposed rules and regulations governing their operation....
 ...The rules and regulations were tentatively adopted by the Commission. The tests of the apparatus made by the Commission's field offices have indicated that if the rules and regulations are strictly complied with the devices may be used without causing interference to established radio services.


1947:
SPECIAL STUDIES
A study was instituted to reclassify and to adopt rules for each class of radio frequency generator now operating under the low power rules, such as phonograph oscillators, remote control devices, and college and utility carrier systems. The rapid increase in the number of such devices since the war, and their more varied applications, have made such action necessary....

...A toy transmitter placed on the market during the Christmas season was tested and the field intensity was found to be within the requirements of the low-power rule."

1958:
https://www.fcc.gov/reports-research/reports/annual-reports-congress/24th-annual-report-congress-1958
 Page 146 --
INVESTIGATIONS /
UNLICENSED OPERATION
-------------------------------------------------------
"Unlicensed operation....
A wave of unlicensed broadcasting by teen-agers resulted from radio mail order houses and popular magazines advertising low-power radio communication kits intended for operation without a license. These "do it yourself" sets radiated excessively and caused interference when augmented with an antenna:

- In a Massachusetts town, youthful radio enthusiasts were found operating a "wireless broadcast" network built from kits.

- In Grand Rapids, Mich., four miniature transmitters were used by youths to broadcast phonograph records.

- At a western university, boys living in a dormitory operated phonograph oscillators as unlicensed transmitters to serenade the girls in a sorority house.

Advertisers of low-power "broadcast kits" have been requested to include with their sets warnings that the devices may be operated only in compliance with part 15 of the Commission's rules.

1960:
(page 122)
"An article which appeared in a national youth magazine about a low-powered broadcast station operated by youths in California was responsible for an increase in unlicensed broadcast operation by youngsters.

 In one instance a young man was conducting a "man on the street" interview program over his unlicensed broadcast station and one of the curious on-lookers was an FCC engineer who promptly terminated the operation.

A youth in New England interviewed on a weekend national network program was heard by an alert field engineer and his broadcast station was subsequently closed, only to have his irate father protest to his Senator.


1960
INVESTIGATION
Low Power Communication Devices
Local interference problems are aggravated by persons who operate low-power communication devices which exceed the radiation limits prescribed in part 15 of the Commission's rules. Unlicensed use of wireless microphones, phonograph oscillators, electronic "baby sitters," home intercommunication systems, remote control of model airplanes, etc., is permitted on certain frequencies but under strict limitations as to power, antenna length and radiation. But many of these operations exceed the limits and interfere with licensed radio services.
This is especially true of juveniles using mail order kits of home-assembled equipment to "broadcast" voice and records to a neighborhood. Besides taking action against violators, the Commission continues to seek the cooperation of manufacturers, sellers, and users of such devices to see that they ate certified as meeting technical requirements.

Carrier Current Broadcast Systems
There is continued interest on the part of colleges, churches, and individuals to establish carrier current broadcast systems or to increase the power of existing systems. However, to avoid interference to licensed broadcast stations, section 15.7 of the rules limits radiation so that associated receivers must either be connected directly to the distribution cable or in close proximity. Sampling investigations over the years have consistently indicated a tendency to exceed the allowable radiation limits.
 Operators have been warned of the consequences that could result from excessive radiation, but there is particular difficulty with colleges because of changing student bodies in charge of so-called "campus" broadcast systems. Lack of personnel has made it impossible to investigate the carrier current systems at all colleges. The Commission is studying proposals in docket 9288 for possible amendments to the existing regulations.

Type Acceptance of Transmitters
The Commission's type-acceptance program is designed to evaluate the technical adequacy of transmitters used in most of the radio services.
Type acceptance is based upon evaluation of descriptive and measurement data usually furnished by the manufacturer, or occasionally by the applicant for license. If such data show that the transmitter is capable of meeting the technical specifications of the rules governing the class of station for which the transmitter is designed, type acceptance is granted.

 If circumstances warrant, the Commission may require that type-accepted equipment be submitted to its laboratory for inspection and test to substantiate its capability of compliance with applicable rules.
The Commission's type-acceptance data and other information on equipment filed for application reference purposes are not open to the public but are useful to the Commission in determining the technical characteristics and capability of transmitters.
Applicants who have once filed such data can iudicate on subsequent applications that the infonnation is already "on file."