FCC 73.683 Revised as of October 1, 2006
Goto Year:2005 |
2007
Sec. 73.683 Field strength contours and presumptive determination of field
strength at individual locations.
(a) In the authorization of TV stations, two field strength contours are
considered. These are specified as Grade A and Grade B and indicate the
approximate extent of coverage over average terrain in the absence of
interference from other television stations. Under actual conditions, the
true coverage may vary greatly from these estimates because the terrain over
any specific path is expected to be different from the average terrain on
which the field strength charts were based. The required field strength, F
(50,50), in dB above one micro-volt per meter (dBu) for the Grade A and
Grade B contours are as follows:
------------------------------------------------------------------------
Grade A Grade B
(dBu) (dBu)
------------------------------------------------------------------------
Channels 2-6.................................... 68 47
Channels 7-13................................... 71 56
Channels 14-69.................................. 74 64
------------------------------------------------------------------------
(b) It should be realized that the F (50,50) curves when used for Channels
14–69 are not based on measured data at distances beyond about 48.3
kilometers (30 miles). Theory would indicate that the field strengths for
Channels 14–69 should decrease more rapidly with distance beyond the horizon
than for Channels 2–6, and modification of the curves for Channels 14–69 may
be expected as a result of measurements to be made at a later date. For
these reasons, the curves should be used with appreciation of their
limitations in estimating levels of field strength. Further, the actual
extent of service will usually be less than indicated by these estimates due
to interference from other stations. Because of these factors, the predicted
field strength contours give no assurance of service to any specific
percentage of receiver locations within the distances indicated. In
licensing proceedings these variations will not be considered.
(c) The field strength contours will be considered for the following
purposes only:
(1) In the estimation of coverage resulting from the selection of a
particular transmitter site by an applicant for a TV station.
(2) In connection with problems of coverage arising out of application of
Sec. 73.3555.
(3) In determining compliance with Sec. 73.685(a) concerning the minimum field
strength to be provided over the principal community to be served.
(d) For purposes of determining the eligibility of individual households for
satellite retransmission of distant network signals under the copyright law
provisions of 17 U.S.C. 119(d)(10)(A), field strength shall be determined by
the Individual Location Longley-Rice (ILLR) propagation prediction model.
Guidance for use of the ILLR model for these purposes is provided in OET
Bulletin No. 72. This document is available through the Internet on the FCC
Home Page at http://www.fcc.gov.
(e) In the case of measurements to determine the eligibility of individual
households to receive satellite retransmission of distant network signals
under the copyright law provisions of 17 U.S.C. 119(d)(10), if a satellite
carrier and the network station or stations asserting that the
retransmission of a signal of a distant network station is prohibited are
unable to agree on a person to conduct the test, the American Radio Relay
League, Inc., 225 Main Street, Newington, CT 06111–1494, shall designate the
person or organization to conduct measurements based on the technical
qualifications and independence of proposed testers. The satellite carrier
and network station shall propose testers and provide their qualifications
in writing to the American Radio Relay League (ARRL). Individuals may also
volunteer themselves as testers by submitting their qualifications to the
ARRL. The ARRL can be reached by telephone at 860–594–0200, or email at
hq@arrl.org.
(f) A satellite carrier is exempt from the verification requirements of 47
U.S.C. 339(c)(4)(A) with respect to a test requested by a satellite
subscriber to whom the retransmission of the signals of local broadcast
stations is available under 47 U.S.C. 338 from such carrier. The definitions
of satellite carrier, subscriber, and local market contained in 47 CFR
76.66(a) apply to this paragraph (f).
[ 44 FR 36039 , June 20, 1979, as amended at 47 FR 35990 , Aug. 18, 1982; 50 FR 23699 , June 5, 1985; 50 FR 32416 , Aug. 12, 1985; 65 FR 36641 , June 9, 2000;
70 FR 21670 , Apr. 27, 2005]
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