BriarTek Inc. ORCADSC Manual De Usuario

Descargar
Página de 9
 
3
Figure: 1
 
Introduction 
 
ORCA
®
 is a personal saltwater or manual-activated man overboard (MOB) alarm system 
developed by BriarTek Inc. The system is utilized by the U.S. Navy and other mariners to aid in 
the rescue of an MOB victim and includes a transmitter, receiver, and direction finder.  The 
ORCA
®
 DSC transmitter alerts a MOB event on VHF marine channel 70 and 121.5 MHz.  When 
the transmitter is activated, it transmits a digital selective calling (DSC) distress message on VHF 
marine channel 70 from the victim to any vessel operating with a DSC complaint VHF marine 
radio.  ORCA
®
 DSC also transmits a distress message to an ORCA
®
 receiver on 121.5 MHz 
during a MOB event.  The receiver emits an audible alarm and displays the ship type/hull number 
and serial number of the transmitter on the ORCA
®
 receiver’s LCD.  The transmitter also emits a 
signal that is received by the direction finder and other standard search and rescue (SAR) 
equipment to locate the MOB.    
ORCA® DSC  Parts Overview 
(See figure 1)
 
A - Antenna 
B - Manual activation/ deactivation recess 
C - Water sensors  
D - Distress marker light (DML) 
E – Battery door 
 
Modes 
The ORCA® DSC has three modes:  
♦  ARMED - Each transmitter is ARMED after 
a 3 volt CR123 lithium battery is correctly 
installed.   
♦  TRANSMIT - The transmitter goes from 
ARMED to TRANSMIT mode when it is 
automatically activated by submerging it in 
saltwater for a minimum of 3 seconds or 
when it is manually activated.  After the 
transmitter is activated, it emits a DSC 
message on VHF marine channel 70 per the ITU-R M.493-11 protocol to its registered 
VHF marine radio.  It repeats this message every five minutes for 30 minutes.  If the unit 
has not been turned off after 30 minutes, it will then transmit a group distress message to 
DSC equipped radios within range of the transmitter.  The unit also transmits a FM distress 
signal at 121.5MHZ after the initial DSC transmission.  This sends the transmitter 
identification to the ORCA
®
 receiver.  After sending this FM distress message for 
approximately 1 minute, the transmitter switches to a non-data transmission for 40 
seconds. This allows the DF to track the transmitter more effectively.  After every 40 
second non-data transmission, the unit transmits identification information to the ORCA
®
 
receiver for 9-15 seconds.   
♦  DISABLED - The transmitter is DISABLED when the battery is removed or the battery 
runs out.