§  90.427   Precautions against unauthorized operation.

   (a) Each transmitter shall be so installed and protected that it is not
   accessible to or capable of operation by persons other than those duly
   authorized by and under the control of the licensee. Provisions of this
   part authorizing certain unlicensed persons to operate stations, or
   authorizing unattended operation of stations in certain circumstances,
   shall not be construed to change or diminish in any respect the
   responsibility of station licensees to maintain control over the
   stations licensed to them (including all transmitter units thereof), or
   for the proper functioning and operation of those stations and
   transmitter units in accordance with the terms of the licenses of those
   stations.

   (b) Except for frequencies used in accordance with § 90.417, no person
   shall program into a transmitter frequencies for which the licensee
   using the transmitter is not authorized.

   [ 43 FR 54791 , Nov. 22, 1978, as amended at  52 FR 47570 , Dec. 15, 1987]