Sec. 90.627  Limitation on the number of frequency pairs that may be 
          assignable for trunked systems and on the number of trunked 
          systems.

    (a) The maximum number of frequency pairs that may be assigned at 
any one time for the operation of a trunked radio system is twenty, 
except as specified in Sec. 90.621(a)(1)(iv).
    (b) No non-SMR licensee will be authorized an additional trunked 
system within 64 kilometers (40 miles) of an existing trunked system, 
except where:
    (1) The additional trunked system will be used to provide radio 
facilities for a single entity, where the additional system is justified 
on the basis of the requirements of the proposed single user; or,
    (2) The licensee's existing trunked system is loaded to at least 70 
mobile and control stations per channel.
[ 47 FR 41032 , Sept. 16, 1982, as amended at  48 FR 44559 , Sept. 29, 1983; 
 48 FR 51929 , Nov. 15, 1983;  49 FR 36377 , Sept. 17, 1984;  51 FR 37404 , 
Oct. 22, 1986;  53 FR 12157 , Apr. 13, 1988;  58 FR 44963 , Aug. 25, 1993; 
 59 FR 59966 , Nov. 21, 1994]