Why would I want or need an NMEA Opto-isolator adaptor cable?
Simply put, to protect your computer investment – if the serial communications port on a laptop is damaged, it is normally a very expensive repair that could require replacement of the entire motherboard. This cable allows easy, safe and low-cost connection of an NMEA 0183 system (or any other compatible RS422 / RS485 system) to a laptop or PC, by matching a standard RS232 D-type 9-pin serial port to an NMEA 0183 type marine bus link.
Potentially damaging voltage or current spikes can be present in the electrically noisy environment of the vessels wiring network – alternators, motors etc. can induce or conduct very large voltage and current spikes into the vessels power cables; computer ports (RS232, USB etc.) are designed to handle low voltage and low current signals only and are easily to damage in the marine environment.
This adapter cable needs no external power supply as the interface takes all its power from the computer port. Once the cable is wired to the NMEA 0183 network, and the connector plugged into the computer, the data will be available via its serial communications port.
If you require more flexibility for a RS232 / computer source to add its own NMEA data to the NMEA network, the Actisense NMEA Multiplexer (NDC-4) will fulfill most if not all requirements.