Specifications

74
8.2.8
Test VHF transmission
The communications test is used to verify the operation of the VHF communication by transmitting a request
for an acknowledgement to another ship (a.k.a. “pinging”). The user can select an AIS target from the list in
AIS 2 screen as long as the target is a Class A AIS transponder and “ping” it. This can be done under the AIS 4
screen. You can send a TEST text message to any class A AIS target and hopefully it will send an
acknowledgement message back. If the Acknowledgment is not received within 10 seconds, an alarm
message will be sounded. It is possible that the Communications Test has failed or the auto ACK feature of
the AIS target has not been activated. The user should retry with another target.
If the MX535B is in “Silent mode”, it is not possible to perform this test:
Using the AIS 2 screen, you can pick a target number using the TGT index number and use that to “ping”.
To “ping” a target, do the following:
1. Press the AIS key several times until the AIS 4 screen appears.
2. Press the EDIT key to bring up the cursor to “TGT:” field.
3. Enter the index (or TGT# i.e. #3) number of the target vessel as listed in the AIS 2 screen.
4. The MMSI field will be populated with the MMSI# for the selected vessel.
5. Scroll down to the text string field and type the word “TEST” using the alphanumeric keypad.
6. Highlight the “Tx MSG” softkeys using the left (or right) arrow key.
7. Press the ENT key to transmit.
8. Press the EDIT key to exit.
9. Press the right arrow key to bring up AIS 5 screen. If the pinged target sends an acknow-
ledgement, the word YES will be indicated under the ACK field. If no acknowledgement is
received within 10 seconds, the word NO will be indicated and an alarm message will be
shown on the display.