Ingangsdatum: 23-11-1996
1 FREQUENCIES AND CLASSES OF EMISSION
1.1 The receiver should be capable of being tuned
throughout the bands between 1,605 kHz and 27.5 MHz. Tuning should be either
continuous, or by incremental steps, or by the selection of a number of spot
frequencies considered by the Administration as adequate for the operation of the
ship, or by any combination of these methods. As a minimum, the following
frequencies should be readily accessible to the operator: the carrier frequencies
2,182, 4,125, 6,215, 8,291, 12,290 and 16,420 kHz for radiotelephony; the NBDP
frequencies 2,174.5, 4,177.5, 6,268, 8,376.5, 12,520 and 16,695 kHz; and the DSC
frequencies 2,187.5, 4,207.5, 6,312, 8,414.5, 12,577 and 16,804.5 kHz.
1.2 Radiotelephone frequencies should be
designated in terms of the carrier frequency; NBDP and DSC frequencies should be
designated in terms of the assigned (centre) frequency. The selected receiver
frequency should be clearly identifiable on the control panel of the equipment.
1.3 The receiver should be capable of
receiving upper sideband signals as appropriate for classes of emission J3E, H3E,
J2B and F1B.
1.4 The class of emission
should be selectable by not more than one control.
1.5 It should be possible for the user to select reception
frequencies independent of any transmitter setting. This does not preclude the use
of transceivers.
1.6 The receiver should
be capable of being tuned to different frequencies quickly, and in any event within
a period not exceeding 15 s.
2 FREQUENCY
STABILITY AND ACCURACYThe receiver frequency should at all times remain within 10 Hz of
the required frequency following the warming-up period.
3 USABLE SENSITIVITYFor classes of emission J3E and F1B the sensitivity of the
receiver should be equal to or better than 6 μV e.m.f. at the receiver input for a
signal-to-noise ratio of 20 dB. For NBDP and DSC an output character error rate of
10
-2 or less should be obtained for a signal-to-noise ratio of 12 dB.
4 RECEIVER OUTPUT4.1 For the reception of voice signals,
the receiver should be suitable for use with a loudspeaker and a telephone handset
and should be capable of providing power of at least 2 W to the loudspeaker and at
least 1 mW to the handset.
4.2 An output
should be provided for NBDP and DSC signals if the corresponding facility is not
integrated.
5 PERMISSIBLE WARMING-UP
PERIODThe equipment should be capable of operating within 1 min after
switching on.
6 IMMUNITY TO INTERFERENCEThe immunity to interference of the receiver should be such that
the wanted signal is not seriously affected by unwanted signals.
7 CONTROLSThe receiver should be provided with automatic gain control.
8 POWER SUPPLYIf the receiver includes parts which are required to be heated in
order to operate correctly, for example crystal ovens, the power supplies to the
heating circuits should be so arranged that they can remain operative when other
supplies to or within the equipment are switched off. If a special switch for the
heating circuits is provided, its function should be clearly indicated; it should
normally be in the "on" position and be protected against inadvertent operation. The
correct operating temperature should be reached within a period of 30 min after the
application of power.