AIS operation

What are some recommended best practices for checking the correct operation of the AIS at all times?

A practical and straightforward way to confirm good operation is as follows:

First, check if targets at distances greater than 25NM can be steadily and correctly shown on your AIS display. This suggests that the sensitivity of your AIS receiver is acceptable.

Then, contact a couple of those further-than-25NM targets on the VHF and ask them if they too can see your vessel steadily and correctly on their AIS display. This suggests that the output power and antenna efficiency of your AIS transmitter are also acceptable.

If the second step fails, try to disconnect and reconnect the power feed to your AIS and check again before assuming that your transmitter is faulty.