Sec. 76.619  Grandfathered Operation in the frequency bands 108-136 and 
          225-400 MHz.

    All cable television systems operating in a grandfathered status 
under Sec. 76.618 of the Rules and transmitting carriers or other signal 
components capable of delivering peak power equal to or greater than 
10-5 watts at any point

[[Page 558]]

in the cable system in the frequency bands 108-136 and 225-400 MHz for 
any purpose are subject to the following requirements:
    (a) The operator of the cable system shall notify the Commission 
annually of all signals carried in these bands, noting the type of 
information carried by the signal (television, aural, or pilot carrier 
and system control, etc.). The timely filing of FCC Form 325, Schedule 
2, will meet this requirement.
    (b) The operator of the cable system shall notify the Commission of 
the proposed extension of the system radius in these bands. Notification 
shall include carrier and subcarrier frequencies, types of modulation, 
the previously notified geographical coordinates, the new system radius 
and the maximum peak power occurring at any location in the cable 
distribution system. No system shall extend its radius in these bands 
without prior Commission authorization.
    (c) The operator of the cable system shall maintain at its local 
office a current listing of all signals carried in these bands, noting 
carrier and subcarrier frequencies, types of modulation, and maximum 
peak power which occurs at any location within the cable distribution 
system.
    (d) The operator of the system shall provide for regular monitoring 
of the cable system for signal leakage covering all portions of the 
cable system at least once each calendar year. Monitoring equipment and 
procedures shall be adequate to detect leakage sources which produce 
field strengths in these bands of 20 microvolts per meter at a distance 
of 3 meters. The operator shall maintain a log showing the date and 
location of each leakage source identified, the date on which the 
leakage was eliminated, and the probable cause of the leakage. The log 
shall be kept on file for a period of two (2) years, and shall be made 
to authorized representatives of the Commission on request.
    (e) All carrier signals or signal components capable of delivering 
peak power equal to or greater than 10-5 watts must be 
operated at frequencies offset from aeronautical radio services operated 
by Commission licensees or by the United States Government or its 
agencies within 111 km (60 nautical miles) of any portion of the cable 
system as given in paragraph (f) of this section. (The limit of 111 km 
may be increased by the Commission in cases of ``extended service 
volumes'' as defined by the Federal Aviation Administration or other 
federal government agency for low altitude radio navigation or 
communication services). If an operator of a cable system is notified by 
the Commission that a change in operation of an aeronautical radio 
service will place the cable system in conflict with any of the offset 
criteria, the cable system operator is responsible for eliminating such 
conflict within 30 days of notification.
    (f) A minimum frequency offset between the nominal carrier frequency 
of an aeronautical radio service qualifying under paragraph (d) of this 
Section and the nominal frequency of any cable system carrier or signal 
component capable of delivering peak power equal to or greater than 
10-5 watts shall be maintained or exceeded at all times. The 
minimum frequency offsets are as follows:

                                                                        
------------------------------------------------------------------------
                Frequencies                   Minimun frequency offsets 
------------------------------------------------------------------------
108-118 MHz...............................  (50+T) kHz.                 
328.6-335.4 MHz...........................                              
108-136 MHz...............................                              
225-328.6 MHz.............................  (100+T) kHz.                
335.4-400 MHz.............................                              
------------------------------------------------------------------------


In this table, T is the absolute value of the frequency tolerance of the 
cable television signal. The actual frequency tolerance will depend on 
the equipment and operating procedures of the cable system, but in no 
case shall the frequency tolerance T exceed &177;25 kHz in the 
bands 108-136 and 225-400 MHz.

[ 50 FR 29401 , July 19, 1985]