§  23.23   Use of frequencies for radio-telegraph communication within the
continental United States.

   Licensees of point-to-point radiotelegraph stations may use any
   frequency authorized in a station license for communication between
   designated points within the 48 contiguous states and the District of
   Columbia upon the express condition that the use of any frequency above
   5000 kHz shall be subject to the limitation that no interference shall
   be caused to the international service, or to service with Alaska or
   Hawaii; and in the event such interference is caused the licensee shall
   immediately discontinue the use of the frequency or frequencies
   producing such interference and operation thereon may be conducted only
   at times when such interference will not be caused.