Sec. 80.375  Radiodetermination frequencies.

    This section describes the carrier frequencies assignable to 
radiodetermination stations. Only direction finding radar stations will 
be authorized on land.
    (a) Direction finding frequencies. The carrier frequencies 
assignable to ship stations for direction finding operations are:

                            Carrier frequency

410 kHz
500 kHz
2182 kHz
8364 kHz
121.500 MHz
243.000 MHz

    (1) Except in distress the assigned frequency for direction finding 
is 410 kHz;
    (2) Ship stations may use 500 kHz for direction finding exclusively 
in Regions 1 and 3 outside areas of heavy radio traffic. Use must not 
interfere with distress urgency and safety signals or calls and replies.
    (b) Radiodetermination frequencies for cable-repair ships. Except in 
Region 1 the channels in the 285-325 kHz band are assignable to ship 
stations for

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cable-repair radiodetermination operations. In Region 1 the channels 
available for assignment for such operations are limited to the 285-315 
kHz band. The conditions of use of these channels are set forth in 
subpart X of this part. Channel usage must comply with the following 
requirements:
    (1) They are not permitted within the territorial waters of a 
foreign country;
    (2) Their output power must not exceed 15 watts; and
    (3) They must not cause interference to any maritime station in the 
radionavigation service.
    (c) Radiodetermination frequencies below 500 MHz. The frequencies 
154.585 MHz, 159.480 MHz, 160.725 MHz, 160.785 MHz, 454.000 MHz and 
459.000 MHz are authorized for offshore radiolocation and associated 
telecommand operations under a ship station license provided:
    (1) The use of these frequencies is related to the ship's commercial 
operations;
    (2) The station antenna height does not exceed 6 meters (20 feet) 
above sea level in a buoy station or 6 meters (20 feet) above the mast 
of the ship in which it is installed.
    (d) Radiodetermination frequency bands above 2400 MHz. (1) The 
radiodetermination frequency bands assignable to ship and shore stations 
including ship and shore radar and transponder stations are as follows: 
2450-2500 MHz; 2900-3100 MHz; 5460-5650 MHz; 9300-9500 MHz; and 14.00-
14.05 GHz.
    (2) Assignment of these bands to ship and coast stations are subject 
to the following conditions:
    (i) The 2450-2500 MHz band may be used only for radiolocation on the 
condition that harmful interference must not be caused to the fixed and 
mobile services. No protection is provided from interference caused by 
emissions from industrial, scientific, or medical equipment;
    (ii) The use of the 2900-3100 MHz, 5470-5650 MHz and 9300-9500 MHz 
bands for radiolocation must not cause harmful interference to the 
radionavigation and Government radiolocation services. Additionally, the 
use of the 2900-3000 MHz band for radiolocation must not cause harmful 
interference to the Government meteorological aids service.
    (iii) In the 2920-3100 MHz and 9320-9500 MHz bands the use of fixed-
frequency transponders for radionavigation is not permitted;
    (iv) Non-Government radiolocation stations may be authorized in the 
5460-5470 MHz band on the condition that harmful interference shall not 
be caused to the aeronautical or maritime radionavigation services or to 
Government radiolocation service;
    (v) The use of the 5460-5650 MHz band for radionavigation is limited 
to shipborne radar;
    (vi) The use of the 14.00-14.05 GHz band will be authorized only for 
test purposes and maritime radionavigation on a secondary basis to the 
fixed-satellite service; and
    (vii) Selectable transponders must be authorized under Part 5 of the 
Commission rules until technical standards for their use are developed.
    (3) In addition to the conditions in (2) of this paragraph ship 
stations are subject to the following conditions:
    (i) Transponders used for safety purposes will be authorized in the 
2900-3100 MHz, 5470-5650 MHz and 9300-9500 MHz bands. Transponders used 
for non-safety purposes will be confined to the 2930-2950 MHz, 5470-5480 
MHz and 9300-9500 MHz subbands only;
    (ii) In the 2900-2920 MHz and 9300-9320 MHz subbands the use of 
radars other than those installed prior to January 2, 1976, is not 
permitted;
    (iii) In the 2920-3100 MHz and 9320-9500 MHz bands non-selectable 
transponders will be authorized only for safety purposes;
    (iv) Non-selectable transponders must not be used to enhance 
detection of marine craft;
    (4) In the 2920-3100 MHz and 9320-9500 MHz bands shore station radar 
transponders used only as racons will be authorized.
    (e) In addition to the other technical requirements contained in 
subpart E of this part search and rescue transponder stations must meet 
the following technical standards contained in the latest international 
Radio Consultative Committee (CCIR) Recommendation 628 titled 
``Technical Characteristics for a

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Search and Rescue Radar Transponder'':
    (1) Operate in the 9300-9500 MHz band;
    (2) Be horizontally polarized at their source;
    (3) Have an effective receiver sensitivity including its antenna 
gain better than -50 dBm;
    (4) Operate within specifications between the temperatures of -20 
and +50 degrees Celsius;
    (5) Operate within specifications for at least 48 hours at 0 degrees 
Celsius without changing batteries;
    (6) Have a sawtooth sweep with a 5 microseconds &177; 0.5 
microseconds rate and return of less than 0.5 microseconds;
    (7) Have a pulse emission of 100 microseconds maximum duration;
    (8) Have a recovery time following excitation of 10 microseconds or 
less;
    (9) Have a delay between receipt of a radar signal and start of 
transmissions of 1.25 microseconds or less;
    (10) Have an antenna whose vertical beamwidth is no less than 25 
degrees and its azimuthal beamwidth is omnidirectional within 2 dB; and
    (11) Suppress interference caused by the interrogating radar 
antenna's sidelobes.
[ 51 FR 31213 , Sept. 2, 1986, as amended at  52 FR 7419 , Mar. 11, 1987;  55 FR 6394 , Feb. 23, 1990;  57 FR 26779 , June 16, 1992;  58 FR 44953 , Aug. 
25, 1993]

                           Ship Earth Stations