139-1988 IEEE Recommended Practice for the Measurement of Radio Frequency Emission from Industrial, Scientific, and Medical (ISM) Equipment Installed on User's Premises
|Organization:||IEEE - Institute of Electrical and Electronics Engineers, Inc.|
|Publication Date:||12 December 1988|
|Page(s):||1 - 20|
|ICS Code (Emission):||33.100.10|
This document describes equipment inspection and radio frequency (rf) electromagnetic field measurement procedures for evaluation of rf industrial, scientific, and medical (ISM) equipment installed in the user's facility. The term, ISM equipment, as used here, includes equipment that generates rf energy for purposes other than radio communications, to cause physical, chemical, or biological changes; for example, industrial heaters (dielectric and induction), medical diathermy, ultrasonic equipment, rf plasma devices, and rf stabilized welders. These procedures are designed to help ensure that the equipment does not interfere with radio communications, navigation, and other essential radio services. The engineer responsible for the measurements should take all reasonable precautions to ensure that the maximum emission from the ISM equipment under test (EUT) has been measured. Radio frequency field-strength measurements of installed ISM equipment may be required if any of the following conditions exist:1) The emission from the EUT was not measured by the manufacturer. 2) Because of its size or special operating conditions, the EUT could not be tested before installation. 3) Installed ISM equipment is suspected of causing interference. 4) ISM equipment has been modified in a way that could affect its rf emissions. 5) As the equipment ages, there is a question about its continued compliance. Etc.
This standard specifies the cutting and perforating dimensions for 35-mm motion-picture film with a KS-type perforation and a perforation pitch of either 0.1866 in or 0.1870 in (4.740 mm or 4.750 mm).
This practice describes the mechanism for the transfer of control messages between tributaries used within a general-purpose communications channel of an interface system which transports data and digital control signals between equipment utilized in the production, post-production, and/or transmiss...
This document describes equipment inspection and radio frequency (rf) electromagnetic field measurement procedures for evaluation of rf industrial, scientific, and medical (ISM) equipment installed in the user's facility. The term, ISM equipment, as used here, includes equipment that generates rf en...
The following topics are dealt with: field intensity measurement; standard measuring method; symbols, units and abbreviations; methods of measurement; antenna design; antenna gain measurements; associated measuring equipment; measurements on production equipment; measurement precautions and factors ...