§ 2.1053   Measurements required: Field strength of spurious radiation.

   (a) Measurements shall be made to detect spurious emissions that may be
   radiated directly from the cabinet, control circuits, power leads, or
   intermediate circuit elements under normal conditions of installation
   and operation. Curves or equivalent data shall be supplied showing the
   magnitude of each harmonic and other spurious emission. For this test,
   single sideband, independent sideband, and controlled carrier
   transmitters shall be modulated under the conditions specified in
   paragraph (c) of § 2.1049, as appropriate. For equipment operating on
   frequencies below 890 MHz, an open field test is normally required,
   with the measuring instrument antenna located in the far-field at all
   test frequencies. In the event it is either impractical or impossible
   to make open field measurements (e.g. a broadcast transmitter installed
   in a building) measurements will be accepted of the equipment as
   installed. Such measurements must be accompanied by a description of
   the site where the measurements were made showing the location of any
   possible source of reflections which might distort the field strength
   measurements. Information submitted shall include the relative radiated
   power of each spurious emission with reference to the rated power
   output of the transmitter, assuming all emissions are radiated from
   halfwave dipole antennas.

   (b) The measurements specified in paragraph (a) of this section shall
   be made for the following equipment:

   (1) Those in which the spurious emissions are required to be 60 dB or
   more below the mean power of the transmitter.

   (2) All equipment operating on frequencies higher than 25 MHz.

   (3) All equipment where the antenna is an integral part of, and
   attached directly to the transmitter.

   (4) Other types of equipment as required, when deemed necessary by the
   Commission.

   [ 39 FR 5919 , Feb. 15, 1974. Redesignated and amended at  63 FR 36599 ,
   July 7, 1998]

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