AIS Target Range

[Chuck - Raymarine - Moderator]

John,

Q1. The E127 indicates the AIS is in silent mode but the Vesper indicates it is transmitting. I checked the E127 and the option to toggle out of silent mode is grayed out.
A1. Raymarine MFDs are neither designed to report nor control the Silent Mode state of a third party Class B AIS transceiver. Accordingly, the state reported by the MFD's AIS transducer status icon may be ignored. The manufacturers of third party Class B AIS transceivers, typically provide a means of physically switching the transceiver in and out of Silent Mode. It is recommended that that AIS transceiver's documentation or its manufacturer be contacted for further information regarding to do so with your third party AIS transceiver.

Q2. I am able to expand range on the Vesper to 48 miles and see targets. On the E127 I can only see target withing a few miles even when I expand the E127 range.
A2. The MFD has no configuration settings limiting the range of targets viewed and should be able to display data associated targets at much greater ranges than 3nm. Does the third party AIS transceiver have a screen on which the presence of AIS targets may be viewed or has a third party device been interfaced to the NMEA 2000 backbone, either of which in turn is reporting vessels at ranges greater than 3nm, but less than 15nm?