FCC 74.1204 Revised as of October 1, 2014
Goto Year:2013 |
2015
§ 74.1204 Protection of FM broadcast, FM Translator and LP100 stations.
(a) An application for an FM translator station will not be accepted
for filing if the proposed operation would involve overlap of predicted
field contours with any other authorized commercial or noncommercial
educational FM broadcast stations, FM translators, and Class D
(secondary) noncommercial educational FM stations; or if it would
result in new or increased overlap with an LP100 station, as set forth:
(1) Commercial Class B FM Stations (Protected Contour: 0.5 mV/m)
Frequency separation Interference contour of proposed translator
station Protected contour of commercial Class B station
Co-channel 0.05 mV/m (34 dBu) 0.5 mV/m (54 dBu)
200 kHz 0.25 mV/m (48 dBu) 0.5 mV/m (54 dBu)
400 kHz/ 600 kHz 50.0 mV/m (94 dBu) 0.5 mV/m (54 dBu)
(2) Commercial Class B1 FM Stations (Protected Contour: 0.7 mV/m)
Frequency separation Interference contour of proposed translator
station Protected contour of commercial Class B1 station
Co-channel 0.07 mV/m (37 dBu) 0.7 mV/m (57 dBu)
200 kHz 0.35 mV/m (51 dBu) 0.5 mV/m (57 dBu)
400 kHz/ 600 kHz 70.0 mV/m (97 dBu) 0.7 mV/m (57 dBu)
(3) All Other Classes of FM Stations (Protected Contour: 1 mV/m)
Frequency separation Interference contour of proposed translator
Protected contour of any other station
Co-channel 0.1 mV/m (40 dBu) 1 mV/m (60 dBu)
200 kHz 0.5 mV/m (54 dBu) 1 mV/m (60 dBu)
400 kHz/ 600 kHz 100 mV/m (100 dBu) 1 mV/m (60 dBu)
(4) LP100 stations (Protected Contour: 1 mV/m)
Frequency separation Interference contour of proposed translator
station Protected contour of LP100 LPFM station
Co-channel 0.1 mV/m (40 dBu) 1 mV/m (60 dBu)
200 kHz 0.5 mV/m (54 dBu) 1 mV/m (60 dBu)
Note to paragraph (a)(4): LP100 stations, to the purposes of
determining overlap pursuant to this paragraph, LPFM applications and
permits that have not yet been licensed must be considered as operating
with the maximum permitted facilities. All LPFM TIS stations must be
protected on the basis of a nondirectional antenna.
(b) The following standards must be used to compute the distances to
the pertinent contours:
(1) The distances to the protected contours are computed using Figure 1
of § 73.333 [F(50,50) curves] of this chapter.
(2) The distances to the interference contours are computed using
Figure 1a of § 73.333 [F(50,10) curves] of this chapter. In the event
that the distance to the contour is below 16 kilometers (approximately
10 miles), and therefore not covered by Figure 1a, curves in Figure 1
must be used.
(3) The effective radiated power (ERP) to be used is the maximum ERP of
the main radiated lobe in the pertinent azimuthal direction. If the
transmitting antenna is not horizontally polarized only, either the
vertical component or the horizontal component of the ERP should be
used, whichever is greater in the pertinent azimuthal direction.
(4) The antenna height to be used is the height of the radiation center
above the average terrain along each pertinent radial, determined in
accordance with § 73.313(d) of this chapter.
(c) An application for a change (other than a change in channel) in the
authorized facilities of an FM translator station will be accepted even
though overlap of field strength contours would occur with another
station in an area where such overlap does not already exist, if:
(1) The total area of overlap with that station would not be increased:
(2) The area of overlap with any other station would not increase;
(3) The area of overlap does not move significantly closer to the
station receiving the overlap; and,
(4) No area of overlap would be created with any station with which the
overlap does not now exist.
(d) The provisions of this section concerning prohibited overlap will
not apply where the area of such overlap lies entirely over water. In
addition, an application otherwise precluded by this section will be
accepted if it can be demonstrated that no actual interference will
occur due to intervening terrain, lack of population or such other
factors as may be applicable.
(e) The provisions of this section will not apply to overlap between a
proposed fill-in FM translator station and its primary station
operating on a first, second or third adjacent channel, provided That
such operation may not result in interference to the primary station
within its principal community.
(f) An application for an FM translator station will not be accepted
for filing even though the proposed operation would not involve overlap
of field strength contours with any other station, as set forth in
paragraph (a) of this section, if the predicted 1 mV/m field strength
contour of the FM translator station will overlap a populated area
already receiving a regularly used, off-the-air signal of any
authorized co-channel, first, second or third adjacent channel
broadcast station, including Class D (secondary) noncommercial
educational FM stations and grant of the authorization will result in
interference to the reception of such signal.
(g) An application for an FM translator or an FM booster station that
is 53 or 54 channels removed from an FM radio broadcast station will
not be accepted for filing if it fails to meet the required separation
distances set out in § 73.207 of this chapter. For purposes of
determining compliance with § 73.207 of this chapter, translator
stations will be treated as Class A stations and booster stations will
be treated the same as their FM radio broadcast station equivalents. FM
radio broadcast station equivalents will be determined in accordance
with § § 73.210 and 73.211 of this chapter, based on the booster
station's ERP and HAAT. Provided, however, that FM translator stations
and booster stations operating with less than 100 watts ERP will be
treated as class D stations and will not be subject to intermediate
frequency separation requirements.
(h) An application for an FM translator station will not be accepted
for filing if it specifies a location within 320 kilometers
(approximately 199 miles) of either the Canadian or Mexican borders and
it does not comply with § 74.1235(d) of this part.
(i) FM booster stations shall be subject to the requirement that the
signal of any first adjacent channel station must exceed the signal of
the booster station by 6 dB at all points within the protected contour
of any first adjacent channel station, except that in the case of FM
stations on adjacent channels at spacings that do not meet the minimum
distance separations specified in § 73.207 of this chapter, the signal
of any first adjacent channel station must exceed the signal of the
booster by 6 dB at any point within the predicted interference free
contour of the adjacent channel station.
(j) FM translator stations authorized prior to June 1, 1991 with
facilities that do not comply with the predicted interference
protection provisions of this section, may continue to operate,
provided that operation is in conformance with § 74.1203 regarding
actual interference. Applications for major changes in FM translator
stations must specify facilities that comply with provisions of this
section.
[ 55 FR 50694 , Dec. 10, 1990, as amended at 56 FR 56170 , Nov. 1, 1991;
58 FR 42025 , Aug. 6, 1993; 65 FR 7649 , Feb. 15, 2000; 65 FR 67304 , Nov.
9, 2000; 65 FR 79780 , Dec. 20, 2000]
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