SAILOR RT4822 VHF-DSC ( Skanti 1000 )

The SAILOR RT4822 is a marine VHF radiotelephone with integrated DSC Class A, developed for SAILOR System 4000 GMDSS installations. The unit provides VHF voice communication, DSC signalling, NMEA 0183 navigation input, external loudspeaker connectivity and SPARC-Bus system integration.

The RT4822 operates in the 150.8–163.6 MHz marine VHF frequency range and supports simplex and semi-duplex operation. It provides up to 25 W RF output power in high-power mode and approximately 0.9 W in low-power mode.

Technical Specifications

Parameter	Specification
Model	SAILOR RT4822
Equipment Type	VHF / DSC Transceiver
DSC Class	Class A
Frequency Range	150.8 – 163.6 MHz
Channel Spacing	25 kHz
Optional Channel Spacing	12.5 kHz
Standard Channels	International channels, 25 kHz
Private Channels	Up to 40
Optional Channels	Up to 224, including up to 54 private channels
Operating Mode	Simplex / Semi-duplex
Telephony Modulation	G3EJN
DSC Modulation	G2B
Frequency Stability	±10 ppm / optional ±5 ppm
Antenna Connector	50 Ω female SO239
Nominal Supply	13.2 V DC
Supply Range	10.8 – 15.6 V DC
Operating Temperature	-15°C to +55°C
Dimensions	100 × 200 × 176 mm
Transceiver Weight	2.5 kg

The technical specification states compliance with applicable requirements and resolutions from ETSI, IEC, ITU and IMO, including ETS 300 162, ETS 300 338, IEC 945, IEC 1097-3 and IEC 1097-7.

Offered product is reconditioned & tested.

Transmitter

High-power RF output: 25 W
Low-power RF output: 0.9 W
Adjacent-channel power: below -70 dBc
Spurious radiation: below 0.25 µW
Cabinet radiation: below 0.25 µW
Distortion: below 5%
Signal-to-noise ratio: better than 40 dB
AF response: +6 dB/octave

Receiver

Sensitivity: -119 dBm / 0.25 µV at 12 dB SINAD
Audio output 1: 4 W / 4 Ω
Audio output 2: 6 W / 4 Ω
THD: below 5%
Signal-to-noise ratio: better than 40 dB
Spurious emission: below 2 nW
Spurious response attenuation: more than 70 dB
Intermodulation attenuation: more than 68 dB
Co-channel rejection: better than -10 dB
Adjacent-channel selectivity: more than 70 dB
Blocking: more than 90 dBµV

DSC – Digital Selective Calling

The integrated DSC section operates according to ITU-R M.541-6 and ITU-R M.689-2 and uses the ITU-R M.493-7 Class A DSC protocol.

DSC protocol: ITU-R M.493-7 Class A
DSC modulation: 1700 Hz ±400 Hz
Data rate: 1200 baud ±30 ppm
Frequency error: below ±1 Hz
Symbol error rate: below 1 × 10⁻² at -119 dBm / 0.25 µV
Residual DSC modulation: below -26 dB

NMEA 0183 / GPS Interface

The RT4822 includes an NMEA 0183 navigator interface for connection to onboard navigation equipment.

Supported NMEA sentences:

GGA
GLL
ZDA

GPS/NMEA input is available through the Options connector:

Pin 4 – NMEA_IN+
Pin 5 – NMEA_IN-

The manual also specifies connection through the supplied 15-pin high-density D-sub interface using the same NMEA input pins.

Power Supply

The standard RT4822 supply is 12 V DC.

For 24 V DC installations, the manual specifies the use of the SAILOR N420 external power supply, which converts 24 V DC to 13.2 V DC.

For AC operation, the SAILOR N163S is used together with the N420 for: 110 / 220 V AC

Current consumption specified in the installation manual:

Standby: 0.14 A
Transmit, low power: 1.5 A
Transmit, high power: 5 A

The power connection uses a 10 A mini automotive fuse.

Antenna Connection

The RT4822 uses a 2 pcs standard 50 Ω female SO239 antenna connector.

The installation manual specifies:

50 Ω antenna system
Maximum VSWR: 1.5
Recommended low-loss coaxial cable: RG213U
Antenna connector: PL259

For GMDSS Class A installations, the system uses separate antennas for the primary VHF transceiver and Channel 70 receiver. The primary transceiver antenna should be installed higher than the Channel 70 receiver antenna.

SPARC-Bus and System Connections

The RT4822 provides a SPARC-Bus interface for system interconnection and external control units.

Available system connections include:

Handset
SPARC-Bus
External loudspeaker
Printer
NMEA/GPS
DC power
Antenna

Dimensions

The transceiver dimensions are:

100 × 200 × 176 mm (H × W × D)

The handset weight is approximately 0.4 kg.

Related Part Numbers

SAILOR RT4822 System Components

RT4822 – VHF-DSC Transceiver
MB4994 – Optional Mounting Bracket
80499410 – MB4994 Bracket Part Number
N420 – 24 V DC to 13.2 V DC Power Supply
N163S – AC Power Supply
56.114 – SPARC-Bus / Option Cable, 5 m
56.127 – VHF Printer Cable

Typical Replacement / Service Applications

The RT4822 can be used for:

Replacement of an existing SAILOR RT4822 VHF-DSC
GMDSS VHF-DSC system servicing
VHF-DSC retrofit installations
Replacement of defective transceiver units
Spare equipment for SAILOR System 4000 installations
Marine VHF communication and DSC system maintenance

Note: The exact contents of a supplied unit may vary depending on whether the item is supplied as the transceiver only or as a complete set with handset, mounting hardware and accessories.