| PC 
            Active (NMEA/RS232) Interface Cable 
 If your system was supplied with 
                              a standard NMEA interface cable (9 pin D type connector and 
                              flying leads), then in all probability it will work well. 
                              However in noisy electrical environments or with long cable 
                              runs problems might be encountered. A solution is to use an 
                              active opto-isolated cable, this also reduces the risk of 
                              damage to your laptop during electrical storms (but can never 
                              fully protect)
 
 Most personal computers communicate with the outside world 
                              via a protocol called RS232. NMEA and RS232 operate on slightly 
                              differing signal voltage levels and with some older equipment 
                              there is a danger of unreliable communication and possible 
                              damage to the computer serial port unless a suitable interface 
                              cable is used. Some GPS manufacturers supply suitable cables 
                              with their devices – if you have one of these, do check 
                              that it is fully opto-isolated and that it protects against 
                              reverse polarity before using it.
 The interface cable Euronav supplies allows 
                bi-directional transfer between NMEA and RS232 protocols, 
                typically allowing data to come in to the PC from a GPS receiver 
                or other instrument system, and simultaneously be transmitted 
                to another device, such as an autopilot. As well as converting 
                voltage levels between NMEA and RS232 levels, and protecting 
                against reversed polarity, the listener (input) side is opto-isolated 
                as per the NMEA specification. The electronics may be powered 
                from the PC’s serial port, or from the boat’s 
                12V DC power supply (if your PC is unable to provide sufficient 
                power). The electronics are housed in a 9-pin "D" 
                connector, ready to connect to the serial port of most PCs; 
                the 1m shielded cable has wires at the other end to connect 
                to your NMEA device(s) and to a 12V power supply (if required).
 Note: You will still need the appropriate cable to connect 
                to the NMEA cable to your GPS,as this is specific to each 
                GPS model.
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